Introducing Core Blue by Rapport Golf. The perfect balance of high performance, consistency and reliability. Each shaft is specifically designed utilizing our Zone Frequency Profiling technology that optimizes shaft frequency, weight, torque, profile, launch and spin, to help each golfer hit it as long, as straight and as consistent as possible. The Core Blue line has options for every golfer ensuring the right fit. Fit & Design: Designed using ZFP (Zone frequency profile) technology to optimize performance (distance and dispersion) in todaya (TM)s modern fairway wood designs 100% frequency tested in both 0Adeg and 90Adeg planes Each weight and flex profile are designed to match a specific player profile (based on swing speed and tempo), providing optimal launch and spin for that player type Manufactured from the same high modulus materials as the rapport wood shafts, enhancing feel and consistency