The 6.0 is constructed with a proprietary alloy blend, which makes it the lightest shaft True has manufactured to date clocking in at a paltry 5.3 ounces. True is also more upfront about the strength of their shaft than we have ever seen before, listing their 3 identified key properties on the side of the shaft. In addition to weight, they list tensile strengths in bending and breaking limits dubbed "Ultimate Strength" and "Yield Strength" measured in KPI (kilopound per square inch). Ultimate strength measured in at 98 and Yield at 95. One KSI is equivalent to 1,000 psi of pressure, so it's safe to say True Shafts are built to last.