Information and Q&A About Single Length Irons


The concept of making each iron in a set the same length is not new.  Eric Cook’s Iso-Vibe Golf Company in Canada began offering single length sets of irons to the North American golf market in 1986.  Perhaps the best known introduction of a single length set of golf clubs was the former Tommy Armour Golf Company’s release of their EQL single length woods and irons in 1989.  Since that time, a handful of lesser known, under-marketed companies have offered single length sets of irons, mainly through an on line direct-to-golfer offering.

The concept of single length irons received a huge boost in general awareness from the publicity of amateur golfer Bryson deChambeau’s victories in both the USA National Collegiate Athletic Association (NCAA) and US Amateur championships in 2015 using a single length set of irons.   Bryson deChambeau became only the 5th player to achieve this very prestigious amateur championship “double” in the same year, something that had only been done by Jack Nicklaus, Phil Mickelson, Tiger Woods and Ryan Moore.  All of a sudden a larger number of golfers became aware of single length irons and with it, a serious level of curiosity whether a Single Length set could be a viable change to make in their own equipment.

As is the case with any new and different golf equipment concept that gains awareness and attention, there are a lot of questions as well as a bit of misinformation and misunderstanding concerning single length sets of irons.   As the leader in golf equipment performance research, Tom Wishon Golf Technology is pleased to once again offer the most truthful, factual and understandable information to help golfers understand the concept of Single Length set design.

Following are a number of questions with answers pertaining to the concept and performance of Single Length sets of irons.  If you have questions beyond the following, we welcome you to ask by sending us an email at  .

What is the Reason a Golfer Might Consider Making a Change from Normal Incremental Length Irons to a Single Length Set of Irons?

The technical basis behind the creation of a set of single length irons is to say that if all the clubs have the same length, the same total weight, the same headweight, and the same balance point it will enable the golfer to use the same stance, posture, spine angle, swing plane – the same everything in the swing. As such, the single length approach has a chance to offer a higher level of swing repeatability and shot consistency for each of the clubs in the set.

At the same time, it must be said that many golfers have achieved very good swing and shot consistency using irons built to normal incremental lengths which are very accurately custom fit to their size, strength, athletic ability and swing characteristics.  However, if a golfer has suffered from chronic or occasional shot inconsistency, converting to a single length concept could offer some help.

 What is the Technical Explanation to Support an Argument About Single Length Irons Being Better for a Golfer than Conventional Incremental Length Irons?

 In a single length set of irons, every club is made so that everything that has anything to do with swing feel is the same in each club – same length, same shaft weight, same total weight, same head weight, same swingweight, same balance point, same MOI, and the same shaft stiffness/bend profile design. The only element that is different within single length clubs are the loft angles, to enable the single length clubs to each hit the ball different distances.

Normal incremental length sets of irons cannot duplicate that many different fitting elements.  While it is possible to build incremental length sets of irons to all be matched to the same MOI, each club will be different in total weight, head weight, swingweight, and balance point.

As such, the technical reason for creating a single length set of irons is to offer the golfer a chance for improvement in swing repeatability, swing consistency and shot consistency because every club is as perfectly matched for every possible aspect that has anything to do with swing feel.

Why Did Sets of Irons Evolve to be Made to Different Lengths?

 The purpose of a set of irons is to have each iron hit the ball a specific different distance with equal distance gaps between clubs through the set. That enables a golfer to choose an appropriate club for the different distances golfers will find themselves from the greens when playing a round of golf.

Early club designers learned there were a number of things in the design of irons that would cause each club to hit the ball a different distance.   First is a different loft angle on each iron, with the spacing in degrees of loft the same between each iron.  Second is a progression of different lengths so the golfer’s clubhead speed would intentionally change to coordinate with the different lofts to hit the ball a different distance with each iron.   Third is an increase in the total weight of the irons as they become shorter, which coordinates with the shorter length to cause the golfer to swing the shorter clubs at progressively slower swing speeds.

More recently, research into shot performance has shown that the distance between the different irons in a set comes 80-85% from the loft angle change from club to club, and 15-20% from the length change from club to club through the set.   As such, length change within a set of irons is much less important for a distance difference between irons than are the differences in the loft angles through the set.   This opens the door for a single length set to be a viable alternative to the conventional incremental length set.

Why Haven’t any of the Big Golf Companies Created and Offered a Set of Single Length Clubs?

Chiefly because of a lack of confidence that such a different type of set could garner enough demand to justify the cost of development and marketing to be able to last for 2 or more years in the market. When Tommy Armour Golf offered their single length EQL model, it did not exactly show much in the way of longer term success for the costs associated with its development and promotion.

 Golf has always been a game steeped with traditions.  Golfers as a whole have demonstrated a general and consistent tendency to not deviate too far outside the norm of such traditions in the game.

This is also true when it comes to certain aspects related to golf clubs. It has been proven over and over that developments in the design, shape and concept of golf clubs have to remain within a narrow range of change – if you go too far outside the box of tradition, golfers will reject such changes and will simply refuse to purchase the clubs if they are considered to be “too different”.

Most of the golf companies have believed that a single length set of golf clubs would push things too far in the minds of most golfers so the sets would not be able to sell in a high enough volume to justify the cost of development, inventory and marketing.

If the clubs are all to be made to one Length and one Lie Angle, what is there for golfers to be custom fit in a set of Single Length Irons?

Every one of the key fitting specifications in any set of irons, that’s what – the lofts, lies, shaft flex, shaft bend profile, shaft weight, total weight, headweight feel (swingweight or MOI), grip style and grip size.   Not only that, but it is possible that some golfers could be more comfortable with a slightly different single length than other golfers.   In short, even though the lengths of each iron will be the same, what that length should be as well as each one of the other key fitting specifications should be custom fit and custom built for each golfer.

Single length does NOT mean “one size fits all” in the manner of the way big golf companies sell their clubs in standard form, off the rack.   Single length sets still need to be properly custom fit to each golfer based on their size, strength, athletic ability and swing characteristics.

What About Single Length Clubs for Tall or Short Players? Such Players Regularly are Fit for “overlength” or “underlength” irons in conventional iron sets.  What About “overlength” or “underlength” in Single Length sets? 

That’s an interesting point in Single Length set fitting. Think about it this way, using the following example.  Let’s say you have two golfers and after a fitting analysis for a conventional set of irons, it is determined that Golfer A needs his lengths to be +1” over standard, while Golfer B is best fit into a standard length set.   That means the 5 iron in Golfer A’s set would be 39” while the 5 iron in Golfer B’s set would be 38”.

But let’s say that both Golfers become aware of the Single Length concept and express an interest to be fit into such a set.   And let’s also say that the Single Length set both see is offered in a “standard” single length of 37”.  Does Golfer A need his Single Length set to be 38” since he was advised to use a +1” over standard length in his conventional set of irons?

Probably not, and here’s why.   In Golfer A’s conventional set of irons, 37” is the length of his +1” over length #9 iron.  While in Golfer B’s conventional iron set, 37” is the length of his standard length #7 iron.  Thus it could be said that the 37” single length would be a proper fit for either golfer, even though in a conventional set Golfer A measured to need +1” longer than standard.

Interesting, eh?

In the end, there may be an occasional situation in which a golfer who needs a longer length in a conventional iron set may need the length of a Single Length set to be a bit longer than the length range the set was designed to follow.   However, we do urge clubmakers to try to keep all golfers within this range between 36.5 and 37 inches for purposes of more successfully fitting the golfer to a suitable total weight + headweight feel in the clubs.

Are Single Length Irons Better for Average to Less Skilled Golfers or are they Viable for Good Players as well?

During the time between the mid 1980s and mid 2010s when only a few isolated companies offered single length sets of irons, most people were led to believe that single length irons were more aimed at average to less skilled golfers. It can be said that Bryson deChambeau’s wins in the NCAA and US Amateur pretty much blew that thought out of the water.

As with normal sets of irons aimed at average vs good players, the main differences fall in the areas of traditional vs game improvement iron HEAD designs, coupled with fitting differences in the shafts, total weight, swingweight (headweight feel), lie and grip size/style.   Most companies that offer Single Length irons are not likely to offer multiple clubhead models as they do with conventional length iron models unless the demand for such a delineation in Single Length head model were to become large enough to justify a better player version to contrast to the game improvement version.

What is the Potential Drawback in Using a Set of Single Length Irons vs a Set of Conventional Incremental Length Irons?

There are three primary areas in which previous Single Length irons have fallen short of the performance golfers are used to with their conventional incremental length iron sets.

Depending on the single length chosen, the golfer may lose enough clubhead speed with the lower loft irons to cause a loss of distance for the lower number irons in a Single Length set vs in a conventional length set.

Also depending on the single length chosen, the golfer may find that shot distances with the high loft irons and wedges are longer than the golfer was used to in the conventional length set. This could happen if the single length is more than 1” longer than the length of the high loft irons/wedges in the conventional set.

Following from both #1 and #2 above, the distance gaps between each single length iron could be compressed, shorter than what the golfer was used to with the conventional set of irons.

 It must be noted that the main reason these problems have occurred with previous Single Length iron sets are because the sets were made with conventional steel clubheads with the same lofts and 4* loft gaps used in conventional iron sets, coupled with a single length that was >1” shorter than the low loft iron lengths and >1” longer than the high loft iron lengths in the golfer’s conventional set. In other words, by customizing the length, the lofts and loft gaps, and the clubhead design, it is possible for a modern Single Length set to overcome these previous problems that have been seen with existing Single Length sets.

Can a Conventional Set of Incremental Length Irons be Converted into a Set of Single Length Irons?

Not without either a lot of lead tape on the lower loft heads and a lot of grinding of weight off the higher loft heads in the conventional set.   Not to mention the potential difficulty of bending the lie angle of some of the heads to the required lie for the golfer for the one single length chosen.

In a Single Length set, all the clubheads must be designed and manufactured to be the same exact headweight AND with the same lie angle.  This is a requirement for the Single Length clubs to all end up with the same total weight, same swing weight, same head weight feel and same balance point – the elements that ensure each club exhibits the same swing feel.

Golfers who are interested in a Single Length set are going to have to test hit clubs properly engineered and manufactured for assembly as a Single Length set to be able to try the concept.   It is completely impractical to alter an existing iron set to the Single Length concept.

What About Woods? Can a Single Length Set of Woods Also be a Viable Change for a Golfer to make with his or her Equipment? 

Tommy Armour Golf Company thought so back in 1989 when they introduced the EQL full sets of golf clubs. In the EQL all the woods from driver to 7-wood were made to be the length of a standard 5-wood – 42”.  This became the biggest area of golfer dissatisfaction with the EQL.  While the golfers could hit the 42” driver with improved consistency and accuracy, the much shorter 42” length brought about a significant loss of clubhead speed which resulted in a marked loss of driver distance for most of the golfers who tried the EQL.

Take distance away from the driver and you end up with a very unhappy golfer.  As such this was one of the main things that killed the possible success of the EQL.

With Single Length irons it is possible to change lofts and engineer a higher COR face into the design of the low loft irons to prevent them from losing distance when built to a single length that is shorter than the length of the low loft irons in the conventional set.  Not so with a driver.  Drivers have been at the top of the COR limit in the rules for over 15 years.  And lower loft doesn’t add distance because with the driver, loft has to be matched to the golfer’s clubhead speed to maximize distance for each golfer.

So if you build a driver as short as a 5 wood, for many golfers that will result in a drop in clubhead speed and distance that cannot be made up in any other way other than to go back to a longer length.

Why Haven’t Other Tournament Golfers Begun to Change to Single Length Irons since Bryson deChambeau’s Success in High Level Amateur Tournaments ?

If you think normal amateur golfers cling to tradition and resist change, just wait until you take a look into that trait among tour pros and very serious competitive amateurs. Shoot, there are still a lot of those players clinging to a muscleback blade in their irons!

But one can never say never.  Even though Bryson deChambeau is a top ranked amateur, the day will come when he will move on to the PGA Tour.  If he continues to play well as a pro, you can count on the fact that a few of his fellow pros are going to be very curious to the point of wanting to at least experiment in the off season with a Single Length set.

On the other hand, deChambeau employs a very different swing technique with his Single Length set that may very well cloud and confuse the way other pros look at the possible use of a Single Length set.   Single Length sets do NOT require the Moe Norman Single Plane swing technique to perform as designed.  Bryson deChambeau just happened to combine a Single Length set with his desire to pursue the Single Plane swing technique.

But because deChambeau would be the only player on tour using a Single Length set and the only player using a Single Plane swing, it is possible that other pros may have the mistaken belief that to play a Single length set requires switching to the Single Plane swing technique.  For those who mistakenly adopt this belief, it is unlikely those players will ever touch a Single Length set.

But for pros who understand that a Single Length set could be used with any swing technique, who knows.  Many tour pros have always been known to have a case of “rabbit ears”, meaning when they see someone else using something new and doing well, they get the interest to try it as well in their ongoing search for the perfect club!

Should I Seriously Consider Buying a Set of Single Length Irons?

We’re a little prejudiced at this point at Wishon Golf because we feel the major changes we have made in the design of the Sterling Irons® Single Length clubheads, coupled with our understanding now of the concepts of proper fitting of Single Length sets, we feel it is a possible way for a very high percentage of golfers to gain a little bit to a moderate improvement in swing and shot consistency.

At the same time, we’ll be the first to say that hit testing of the Sterling Irons® Single Length design showed that there will be some golfers for whom switching from a conventional incremental length set to a Single Length set will just be too strange, too different and too weird for lack of a better term.  We certainly expect that a certain number of golfers will hit the Single Length set just fine, but will not be able to mentally get used to the fact that all their irons are the same length and to be played with the same stance and ball position.

That’s precisely why we are strongly advising clubmakers to encourage interested golfers to “try before you buy”.  And by try we mean to take at least 2 to 3 weeks to hit at least a 5, 7, 9 or a #5 and 9 iron from the Single Length set before they make a decision to buy the set.

We know from 2 years of development work that the Sterling Irons® Single Length set does have all the requirements to deliver a seamless transition for shot distance with each club compared to a conventional set, while at the same time offering the main benefit of the Single Length concept of identical swing feel for every club.

• Sterling Irons® #5 is offered in an option between high COR hybrid and high COR iron for different player types.

• Sterling Irons® #5, 6, 7 irons are all high COR face, variable thickness face design, with low CG and slightly stronger lofts to ensure no loss of distance for these clubs compared to their longer length in a conventional set.

• Sterling Irons® #8 through SW are all one piece cast carbon steel body cavity back irons made in 5* loft increments to also ensure not hitting the ball too far for these clubs compared to their slightly shorter lengths in a conventional set.

• Sterling Irons® Single Length is designed to be built to the golfer’s choice of either 37” (Std #7 iron) or 36.5” (Std #8 iron) or in between.  These are shorter lengths than other single length sets by intent to offer better shot consistency and a higher percentage of on center hits for each club.   With the high COR #5, 6, 7 the shorter single length of the Sterling Irons® won’t result in a loss of distance compared to the golfer’s #5, 6, 7 irons in a conventional length set.

• All of the Sterling Irons® clubheads are bendable for lie and loft by +/-4*. Not only is this critical for proper lie angle fitting for every golfer, it is also a way to tweak the distances and distance gaps between irons.    Golfers come in a variety of different clubhead speeds and angles of attack into the ball.   CH Speed and A OF A have a huge bearing on how far a golfer hits any loft and how much distance any loft gap will exhibit between clubs.  With eminent bendability of the Sterling Irons® Single Length clubheads, it will be possible to offer any golfer a final tweak of the lofts to achieve his most comfortable distances with each iron as well as suitable distance gaps between each Single Length club.


  1. I am hitting Acer XV pro irons -7-8-9-pw- and all the rest of my clubs are wishon . I’m looking to change out those irons . Looking for a recommendation for the wishon irons!

    • BILL

      Thanks very much for your interest in our design work. We appreciate that very much. You did not say much about your playing characteristics, swing characteristics, ball striking tendencies so it is pretty hard to pin point one model to recommend for you. I design each iron model on the basis of those elements of the game to try to help golfers identify which model might be better for them and how they play. If you can respond back on this comment thread with some information about your handicap, your strengths and weaknesses in the game, your preferences for model type/shape/design characteristics if you have any, then I would be glad to offer some more specific comments to try to help you. Thanks much,

  2. Curious if you have two different websites? I sent a bunch of my information to a Sterling website and have not heard back yet. I am very interested in getting a set but wanted to discuss my specs first…which I sent on an email over a week ago.

    • Scott

      The website and direct sales business is not owned by Wishon Golf. This is a separate independent business and is not affiliated with Wishon Golf or Diamond Golf International. They purchase the Sterling iron heads from us and they do all of their own fitting advice and custom building of the sets for the orders that come to their website. Same as is the case with other clubmakers with the only difference being these people do all their business on line in their fitting of the Sterling irons design. I have heard that sometimes it can take a few days for them to catch up with emails when the principle is gone but I am sure they will contact you if they have your email.


  3. Tom, I was considering having a set of Sterling irons built and wanted to match hybrids at the same time to avoid gaps in my set. I noticed the 318RS hybrids have less aggressive lofts, which would be great for me as I live in the desert SW and the ground can be hard. My question is, with the higher lofts on the 318RS hybrids, how would the clubs be set up to have a gapless set from the hybrids to irons (sadly, there is no fitter in my area)?

    • Lee
      Transitioning hybrids that by virtue of their head weight are intended to be longer than the length of the single length irons, the first decision comes from knowing what will be your lowest number single length Sterling iron. Choosing what will be your lowest number iron is one of the most important parts of single length iron fitting. When all the irons are 7 or 8 iron length, the low loft irons require a certain clubhead speed to be able to get the ball well up to fly and carry so there can be a full club carry distance between each iron. To be able to have the 19* loft #4 iron in your set, you would need to have a minimum clubhead speed with your current 7 iron of 85mph. To be able to have the 23* loft #5 iron in your set, you would need to have a minimum clubhead speed of 77mph. These speeds are based on the golfer having a normal angle of attack with their 7 and 8 iron of -2 to -3*. If the golfer is more steep than that, then the clubhead speed minimum levels in this advise go up a couple of mph. Hope that makes sense.

      So, let’s cover all the bases and say you start with the 6 iron in your set. Above that could come a 318RS #4 at 25* built to a length that is not less than 1.5″ longer than the length you end up using for the Sterling Irons. So if your irons are 36.5″, this 25* hybrid would be not less than 38″. If your Sterlings are 37″, then the 25* is 38.5″ There are two weight bores in the 318s so if you build to 38″ you still will have enough weight addition capability to reach a normal range of swingweights at 38″ length.

      Then above that hybrid would come the 318-3 but you would want to ask the clubmaker to have the 318-3 ordered with a hand select request for it to be 21* so you can get a 4* gap between it and the 25* hybrid. We can do hand picks for 1* higher or lower loft than the spec. That hybrid would be 1/2″ longer than the 25* hybrid, whatever length it happens to end up being based on your iron length. Then above that hybrid would be a 5 wood probably of 18-19* loft and normal 5 wood length but not longer than 41.5″ so control is enhanced. Then comes the 3w and driver.

      If your lowest loft iron in the Sterlings is the 5 iron, then the club above that would be a 318-3 but with its standard loft of 22* no hand pick needed on that because having a 3* jump from the 5 iron to hybrid is right because the hybrid is longer in length. That added length over the irons makes up the distance difference to allow the loft gap to just be 3*.

      And that should be a good way to manage your set makeup. Hope this helps,

  4. Tom, from what you are saying about lie angle in single length irons being “critical”, how tight of tolerance in the sterling’s? Guessing that I would need to pay for the hand select service to make sure they all are 63 degrees in lie. Would like to add the 4 iron to a sterling set, recently driver swing is 95 might I be safe to say that I am within your 85 speed for 5 iron. I am 6’3”” and hit my 5 iron 190-200? Still using you interflexx wood shafts in fairway woods, would S2S black be closest to your interflexx?

    • GARY

      The stated tolerance is +/-1* but since I have measured literally thousands of Sterling iron heads I can tell you that for the lie 85% are +/-1/2* from the 63* spec while the other 15% are 3/4 to 1* off from the spec. It’s also very similar in loft for each head with 85-90% being less than 1/2* off from the spec and the other 10-15% being 1/2 to 1* off from the loft spec. In the world of clubhead production that really is very good. Most people with a 95mph driver speed are in the area of 77-80 with the iron speed, not as high as 85mph. But if you really do CARRY the ball 190-200 with the 5 iron, then you should be over 85mph and the 4 iron should be ok. Perhaps the driver speed is not accurate then? because most people who hit a 23* loft #5 iron to a carry distance of 190 would have well over a 100mph driver speed. Do you unhinge the wrist hinge angle early on the downswing with the driver but not with the irons? But yes, the Black shaft would be closest to the Interflexx Mid-Low shaft while the White shaft would be closest to the Interflexx High version.

      Thanks again for your interest and best to you in this great game,

  5. Tom,

    Do you have a point of view on the “25 degree golf swing” concept taught by Arlen Bento Jr? I read about it in a USGTF article. The concept is that a simplified more upright swing (25 degrees of forward spine tilt) is very easy to learn and repeat and may help avoid injury. The article discussed a single length set played at 4 iron length (I assume 38.5” in steel).

    It seems like the premise violates the “24/38” rule you discuss in the search for a perfect golf club – however if the average golfer could build their entire game off just a single full swing, perhaps there is merit to it even at that length? Arlen has a very good reputation as a teacher and his students seem to rave about the concept.

    I personally play sterlings 4-sw at 37.5” and have added a second shorter length and weaker lofted SW and a Wishon PCF LW because full swings on the 37.5” wedges can really get out there (hence your recommendation to build them shorter). I play mine an inch over recommended because I like the extra rip I get in long irons at 37.5” and I like that I can hit longer shots with my stock iron swing and replace the dreaded 5 and 7 wood with confidence clubs. I think many other golfers feel the same. I am really curious about what would happen if I added another inch to the set and tested Arlen’s concept?

    Is this something you have a POV on? Worth an experiment to see how I respond as an individual at 38.5”?


    • JOE

      I don’t think there can ever be one type of swing teaching technique that can work well for all golfers because golfers are so very different in their combination of anatomy, physiology, biomechanics, flexibility, muscularity. Some of us can rotate smoothly and consistently in one plane, others in another plane and so forth. Not until some really sharp person skilled in all these fields comes along and figures out a way to analyze each person for these characteristics and then plots that against specific swing techniques will golf instruction really move into the modern era. IMO that is.

      There is no question that people with back pain issues are better off not bending over as much to play the game. Mt bro-in-law is a perfect example with his back issues. I fit him into a set of Sterlings at 37.5″ so he could achieve a posture that took pressure off his back and alleviated his pain somewhat. He’s 6’2 and has an above average wrist to floor measurement and 37.5 was comfortable for him. Bryson deChambeau who I see the 25* site puts on their video as an example is 6’3 and plays 37.5″ length for his single length irons.

      So I do not think you can look at any type of back relief swing technique and automatically say 38.5″ is the right length for all. Besides, as you have discovered, when you go longer with the wedges you do have an issue with distance control. I’m not opposed to teaching people with back issues to be more erect in posture and from it, to swing more upright. But each person is still going to be different in terms of height and arm length for what length is best for them when they are in such a swing technique and thus each person would need to be individually fit for their iron length with this technique.

      As to the 24/38 rule, I intended that to be more about loft than length. But it is just that most lofts go along with a specific length so I chose the 24/38 based on my observations of golfers that many can’t get a 24* loft iron airborne well enough and it just so happens that back when I observed this, most every 24* loft iron was a little longer than 38″. If you had a 38″ club that had 40* loft, most could get it airborne fine. And If you had a 24* loft club at 36″, most still could not get it airborne well enough. So to me this was more about loft than length, but it had to include length because loft + length are so tied together within a narrow range.

      Hope this helps, and thanks for your interest !

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