The Cycle Clinic CC SW05 Shimano Cassette & C-Lock Lockring Tool Fits Centre-Lock Disc rotors and HG cassettes Large internal diameter will fit over all axle locknuts. Can be used with 1/2 inch drive torque wrench or ratchet driver and 21mm spanner. High quality Cr-Mo steel ensures a long lasting tool. where to buyphotogalleryproduct options Photogallery Product options black24"-28" = UA#10000702