Freehub DT Swiss Shimano Microspline Ratchet 12mm DS CapFreehub DT Swiss Shimano Microspline Ratchet 12mm DS Cap A REPLACEMENT FREEHUB BODY The Shimano Micro Spline is needed to run the new Shimano 12 speed mountain cassettes. Freehub bodies will last a long time, but much like all moving parts, it will need to be replaced eventually. The DT Swiss Micro Spline Freehub Body is for ratchet drive hubs and fits DT Swiss 180, 240, 350 hubs. It also includes the adapter for 12 x 142 148mm hubs. Features Designed