SUNRACE CSMZ903 12-SPEED CASSETTE12-speed cassettes used to be just limited to wheels with XD drivers on the back, but now you can use a 12-speed cassette on any mountain bike wheel with the Sun Race MZ90 12-speed 11-51T cassette. It is a wide-ratio cassette that has an alloy spider, lockring, and spacer. It will fit any Shimano or SRAM 8, 9, or 10-speed freehub body, and Shimano Dynasys 11-speed mountain freehub bodies. If you're looking to upgrade and get an ultra-wide range of gears, then look no further than the CSMZ903. Features Works with Shimano HG freehub bodies Ultra-wide range that is perfect for all terrains Cassette Body Type Shimano/SRAM 8, 9, 10-Speed Shimano Dynasys 11-Speed Mountain Cassette Cogs11-13-15-17-19-21-24-28-33-39-45-51Drivetrain Speeds12Weight497 g | Sunrace | Csmz903 12 Speed Cassette | Black Chrome | 11-51T