Sterling Irons Single Length Irons vs. Cobra One Single Length Irons


Hi, I am Tom Wishon and I am a career club head designer.

I have been designing club heads since 1986, during which I’ve had the pleasure to create designs for over three hundred and fifty (350) different models of club heads. One of the more recent models I have had the opportunity to design were the Sterling Irons Single Length iron.

Jaacob Bowden and I debuted the Sterling Irons Single Length irons in spring of 2016.

Well, in the last year one of the major golf club manufacturing companies has also come out with their own model of single length irons…and we got a lot of questions, like:

  • What are the differences between Sterling Irons Single Length Irons and Cobra One Length Single Length Irons?
  • Is one better than the other?

This has been one of my things I have done all my life is written a lot of articles, a lot of books, explaining the technology…and I am very pleased with the fact that I sought to have the ability to explain golf technology in very understandable terms.

So what I want do today is to be able to talk a little bit of the difference between Sterling Irons Single Length and the Cobra One…their version of single length irons.

Club Length

Okay…a few things, the whole concept single length, the Sterling Irons Single Length are based on a standard base club starting with a 36.5” 8-iron length. We chose to do that because in club fitting technology in a golf club design technology the shorter the length you see it is to hit the ball solid on center consistently. In the past, single length irons had all been built around a 6-iron length of 37.5”.

At 8-iron length, that means the Sterling Irons single length iron are fairly easy to hit.

You think about your own 8-iron, if you have a standard length iron…do you feel that you can hit your 8 iron little bit more consistently overall then you can hit you 6 Iron?

Okay…many people do.

Whereas the Cobra One single length set is based on a 37.25”length, which is really half way between the modern standard 6th and 7th iron length, so that makes the Cobra single length irons 3 quarters of an inch longer than a Sterling Irons single length iron. A number of people feel again the shorter the club the easier to hit more consistently…and that is after all one of the big factors with single length.

Single Length vs Conventional

Some also ask should I play a single length set of irons? Or a conventional length model set of irons?

One of the first considerations is…do you hit the iron somewhat inconsistent?

And do you go through periods where you miss a lot?

This is one of the areas where single length set of irons could help. Because with all irons being the same length that means you’re using exactly the same stance, the same posture, the same ball position, and same swing plane.

So you can have a chance to be a little bit more repetitive and potentially achieve a higher level of repeatability with single length.

But with Sterling Irons being 8-iron length 36.5” vs Cobra being 37.25”…this gives a nod to Sterling Irons to be a more consistent set of clubs to hit.

Distance Gapping, Metallurgy, and Face Design

Ok… we also going with that we need to be able to be happy with the distances, as we hit with each of these irons and we need to be able to hit each one of the irons at different specific distances with hopefully the same amount of distance gaps in between each iron in our set.

This has been one of the criticisms that traditionalists in the game try to point the finger at the single length set and say by making all the irons the same length that means you are not getting the higher club head speed for lower loft irons that you do in a conventional Incremental set of irons…that’s true!

And we knew that…I knew that when I was getting into the process of designing these Sterling irons. That’s why I designed the 5, the 6, and the 7-irons in Sterling Irons Single Length set with a genuine thin high strength steel face to create a true High COR performance, to give you more ball speed to make up for a potential loss of distance since your lower loft irons would be shorter in the single length set than they would be in a conventional incremental length set.

I have tremendous experience in my design career with High COR face design, and not just in drivers but fairway woods and hybrid designs.

In fact, I have the pleasure of being the first person to ever design a High COR fairway wood, the first person to design a High COR hybrid, and I was the first person to design a High COR iron in the year 2000.

Since that time, I’ve designed four other sets of normal irons that have High COR faces.

So, I know what I am doing when I am picking a high strength steel…knowing how to be able to create the highest COR from the ball speed relative to your club head speed, making your Sterling Irons set 36.5 inches of length.

This is how we bring back the potential loss of distance with the lower lofted irons by designing a High COR face in the 4, 5, 6, and 7 irons.

The Cobra One irons have attempted to do the same thing but they’ve chosen an alloy…a common stainless steel alloy of 17-4 stainless steel…and they tried thinning out the face to create to give you more ball speed.

It is a little bit more ball speed that you get from conventional normal 17-4 stainless iron head but it doesn’t achieve the higher ball speed, whereas our HS 300 high strength steel gives you for Sterling Irons numbers 4, 5, 6, and 7.

This is a point of metallurgy for the HS300 higher string steel we use in the Sterling Irons single length irons which has a strength of two hundred and seventy five thousand pounds for square inch. 17-4 stainless that is used in Cobra One irons has a strength of one hundred and thirty five thousand PSI, half the strength of the high string steel we are using in a Sterling Irons single length.

Metallurgy and Custom Fitting

In addition, we have created the body of each one of the Sterling Irons single length iron heads from 8620 soft carbon steel.

The Cobra Ones used investment cast 17-4 stainless for the body.

Ok what’s the difference?

Custom fitting is the biggest difference.

You need to be custom fit to play the best of the ability. That’s always been a main stay for the work I have done in my golf club design and it’s been a huge part of the time I have spent in researching custom fitting and writing and teaching the custom club makers how to do this better and better to custom fit golfers.

I chose the 8620 carbon steel for the body of the Sterling Irons single length irons because it can be bent more easily, plus and minus 4 degrees for lie angle changes, or if you need to tweak the loft to fill additional gaps you can bend some of lofts as well.

Club makers will all tell you when they have investment cast 17-4 stainless for the body of the heads like with the Cobra One irons, it is very difficult to bend…and if you can bend it you are only able to bend it to a degree or maybe 2 at the very most.

So the custom lie and loft fitting capability in the Sterling Irons single length irons is more than twice as good is what is in Cobra One irons.

Off the Rack vs Custom Fit

Finally, the biggest difference Sterling Irons Single Length Irons are that they are only sold as custom fit for each golfer.

Sterling Irons single length irons are not put in the any of the pro shops or the retail golf stores where the main form of business is to sell the clubs with one series of standard specifications to be sold on the standard off the rack, which is how the Cobra one single length iron is sold as one standard form to millions of golfers who are completely different from each other in their size, their strength, their athletic ability, and most of all their strength characteristics.

So, with Sterling Irons Single Length, you can only get them custom fit through a club maker or custom fit at

With Cobra it is simply one form off the rack and “we hope you play well with it”.

So these are the key benefits when you want to compare the Sterling Irons single length irons with the Cobra One single length irons.

  • With Sterling Irons you have a shorter single length, which you need for better shot consistently and more consistent on-center hits.
  • With Sterling Irons single length irons, you have a higher COR face on the 4-7 irons to help bring a higher ball speed and give you distance back at the 8-iron length of 36.5 inches.
  • The single length Cobra vs single length Sterling Irons are made with the 8620 soft carbon body for much wider range and bendability for custom fitting for lie and loft. The Cobra ones are cast from 17-4 which is very difficult to bend for loft and lie fitting.
  • And finally, Sterling Irons Single length irons are only available to golfer’s custom fit through club makers or custom fit by Cobra one are primarily sold standard off the rack in golf course retail shops or pro shops.

Those are the key differences and as a thirty-seven year designer of club heads, I really feel that the Sterling Irons Single Length hence are the best single length iron model on the market.

Thanks very much for your interest and a very best year in this great game.