The fact is, no shaft is perfectly round, straight or stiff throughout its length. Despite modern manufacturing techniques every golf shaft, whether steel or composite, remains as unique as a fingerprint and cannot be fully analyzed until after the shaft has been manufactured. These irregularities in construction can significantly impact the performance of a golf club shaft, depending upon its orientation in the clubhead. Improperly aligned, these irregularities can create imbalance, asymmetry, and varying degrees of oscillation during the golf swing. These non-repeating oscillations can and do cause the shaft to bend and twist differently from one swing to the next.
The SST PURE® process involves analyzing the structure of an individual golf shaft and locating the most stable bending plane within that shaft. Using state-of-the-art computer analysis, SST PURE® pinpoints and correctly aligns the shaft's PPOP (Principal Planar Oscillation Plane) in the clubhead to optimize shaft stability and performance -- ensuring the uniform matching of clubs within a set and allowing each club to perform to the best of its manufactured capability.
In the images above, a shaft with a significant ovality is shown in two different orientations. In the non-aligned orientation on the left, the shaft bends down the intended target line across the dominant flex plane of the shaft, causing it to bend and twist erratically. In the PURE aligned orientation on the right, the dominant flex plane is aligned with the target line, allowing the shaft to bend and twist consistently time after time.
Independent research, testing, and statistical analysis show that players of all skill levels, from beginners to touring pros, hit the ball longer, straighter, and more consistently using clubs whose optimal or neutral shaft position has been aligned with the clubhead. The SST patented process of shaft alignment tests and analyzes a golf club shaft to determine its most stable orientation. The process is called PURE®. PURE® is an acronym for Plane of Uniform Repeatability. The result of SST’s process is improved repeatability of hits on the center of the club face.
The SST PURE® equipment generates a printout that accompanies each shaft that provides visible proof that the shaft has been "PUREd" by SST or its licensees. The printout shows the shaft's performance characteristics before and after the PURE process.