Bill Shook’s strong suit is finding answers to industry wide problems. Aluminum cassette bodies are damaged by the individual cassette cogs, and from loose fitting shimano cassettes. Bill Shook’s ingenious answer is his latest patent applied design, the steel faced cassette body. All our shimano style cassette bodies are now equipped with the proven steel face on the splines so that the body will not be damaged by the cassette. Each steel insert is securely dovetailed in place by hand with Bill’s specially designed insert tooling. Steel is harder than aluminum which protects the softer aluminum from being gouged by the cassette. You get the best of both worlds, a light weight aluminum body with the protection of a steel surface. The steel faced cassette will prolong the life of your American Classic hub and make changing cassettes easier. A brilliantly simple solution to an annoying problem. It is Bill Shook’s attention to detail that make American Classic’s wheels better than the rest."Bill Shook came up with a brilliant idea to add a couple of steel inserts on the splines, so that the tougher steel can take the abuse, and you still get the lightweight of the mostly aluminum cassette body. The steel face design is very innovative, and will not only increase the longevity of the cassette body, but it will keep the tolerances tight with better drivetrain performance."