The bottom bracket wrench is used to install or remove the outer bottom bracket cups of the Praxis Works M30 and all other bottom brackets with a cutout diameter of approximately 46.3. The 1/2 square on the tool body allows the use of a torque wrench. material: premium flex plus carbon steel surface finish: chrome plated in accordance with ISO 1456:2009 ergonomic two-component handle Praxis Works TP-0330 Key Replacement