The Blue M1 cassette body fits Easton M1 and X4 hubs and has Shimano HG-E splines for eleven speed Shimano/Sram road cassettes. Use this to put a set of 29er mountain wheels on your disc brake 'cross bike with 11 speed drivetrain.
Fits on M1-121, M1-221, and M1-321 hubs. Does not fit on M1-120 or M1-220, use the orange R4 body for these.