Project X Iron Shaft from True Temper
The Project X design is different from the stepped shafts designs made by True Temper. The EI profile is constant from flex to flex, The stiffness increases as the shaft weight increases. The numbers on the shaft, 5.0, 5.5, 6.0, 6.5 and 7.0 represent stiffness. They are a patented numbering system that dates back to FM Precision. Frequency of the shaft was translated via a linear formula into a stiffness numbering system. A 10 Cycle per Minute, CPM, difference equated to a stiffness number change. When you hear the term frequency matched shafts, it refers to a system, not necessarily the original Braly system, of matching iron set stiffness.
Here is a little history if you are interested, Union Hardware was the first manufacturer of steel golf shafts in the US in 1924. They were acquired in 1956 by Brunswick, which also owned MacGregor golf. Brunswick supplied blanks to FM Precision, a golf shaft company owned by Kim Braly and his dad, Dr. Joe Braly. In 1986 Brunswick acquired FM Precision. At some point, the name was changed to Royal Precision. In the early 2000’s Kim Braly designed the Project X and it quickly gained wide acceptance on tour. In 2006 True Temper acquired Royal Precision and the Project X brand.The Project X is a classic, with too many tour wins count. Until competitive designs emerged, it was for many good players, the shaft of choice. Radial quality and shaft to shaft consistency in the shafts I have checked is excellent. The Project X can be installed in any orientation, being nearly perfectly round, orientation will have no affect on the play-ability of the Project X.