PRO Cassette Wrench Description: The PRO Cassette Wrench is designed as an alternative and more secure tool to a chain whip to aid in the installation and removal of cassettes. Engages the 10 or 11T sprocket to stabilize the cassette to keep it from spinning. Pair this wrench with a favorite lockring tool to perform needed maintenance or upgrades. Features: Alternative to a chain whip Fits 10T and 11T smallest cassette sprokets Hardened steel construction Ergonomic grip allows for proper torque and leverage