Get the shaft that is perfectly fit for your game and your current driver or fairway head! FLEX GUIDE - 5.5 = Regular, 6.0 = Stiff, 6.5 = Extra StiffHZRDUS BLACK - HZRDUS Smoke Black - Featuring a low-spin and low-launch profile that maintains the HZRDUS reputation, Smoke Black is designed for today’s aggressive swingers while providing new optimized material placement to promote an improved feel and increase in playability.HZRDUS Smoke Yellow - HZRDUS Smoke Yellow is a low launch/spin shaft that features a counterbalanced design allowing for mass to be added to the head for maximum ball speeds and higher MOI.HZRDUS Smoke Green - Smoke Green is the latest engineering marvel in the HZRDUS Universe. Being the stiffest HZRDUS shaft yet, Smoke Green is designed to maintain maximum stability and keep up with even the fastest swings.