Are Flex Ratings (L, A, R, S, X) the Same from Company to Company?

Question: Are Flex Ratings (L, A, R, S, X) the Same from Company to Company?

(Editor's Note: Most shaft companies and equipment companies use the same code - L, A, R, S, X - to denote the flex of their shafts. But do all companies call the same flex by the same name? In other words, is one company's "R" flex the same as another's? Are there industry-wide standards for what constitutes each level of flex?)

Answer: No, there is no standard that dictates how stiff any given shaft must be in order to be designated as an L, A, R, S or X shaft.

Shortly after steel shafts were introduced in the 1920s, steel shaft makers discovered they could change the diameter and wall thickness of the tubes to create shafts with different amounts of stiffness to better match to the different swing speeds and strengths of golfers. Eventually, the shaft industry developed five different shaft flex designs, designated by the letters L for Ladies; A for Amateur, which evolved into the senior flex; R for Regular; S for Stiff and X for Extra Stiff.

What is interesting is that no standard for how stiff any of the five flexes would be was ever established in the golf industry.

Still today, each shaft maker develops its own definition for how stiff any of its flex levels will be. As a result, the R flex from one company may be the same or different in comparison to the stiffness of an R flex shaft from another company. The same is true for each of the other four basic flex letter codes.

Thus when selecting the right shaft for your swing mechanics and swing speed, it is important to find a clubmaker or sales person who really knows the differences in shaft flexes to advise on your shaft selection.

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