butt clamp frequency, which make these shafts appear softer than heavier shafts. Three groups of shafts exhibit these characteristics; super lightweight graphite shafts (sub-60g), super lightweight steel shafts (sub 100-gram) and the newer classification of hybrid utility shafts. Most of these shafts will appear to be approximately one full flex softer than their flex designation. This is why it will be important to compare these shafts amongst one another than compare their DNA to heavier weight shafts of different materials.

Many of the manufacturers have job of realizing this so they based their flexes, not by frequency or deflection, but more so by player feedback. So the next time you look at a 55-gram S-flex graphite wood shaft or an S-flex hybrid utility iron shaft and see that the measured flex appears more like an R-flex, realize it will not play like it. Hireko will still continue to provide the data you are accustomed to, but please try to compare like weights to see the difference among the various shafts.