Chris King started making headsets in 1976 and has been refining them ever since. Their DropSet 5 is built to be precise and dependable and sets the standard for quality integrated headset function delivering precision performance that is built on the same pedigree of Chris King headsets from the past 40 years.Compatible with Santa Cruz V10 and other bikes using 41mm upper and lower integrated headset bearingsEngineered, manufactured and assembled in Portland, Oregon USALifetime warrantyLegendary made-in-house bearingsPatented GripLock retention design for exclusively reliable headset adjustment41mm 45x45 upper bearing for 6.85-7.05mm bearing ream depth41mm 45x45 lower bearingCompatible with the included Chris King baseplate or integrated 45 degree crown races