The Cassette Lockring extractor is suitable for assembling and disassembling Shimano HG and compatible cassettes .(normally used together with a chain whip to hold the cassette from rotating. Requires Spanner/Wrench/Vice as the tool does not have a handl.e Suits Dahon and Tern bikes with SOLID AXLE Wheels. Can also be used with Q-release wheels as a cheaper alternative. Various makes supplied according to available stock, but we only supply tools from recognised brands of suitable quality.