Park bottom bracket tool a highly durable metal tool to remove and install shimano hollowtech ii integrated bottom brackets and chainsets key features 16 laser cut splines securely engage the notches of the bottom bracket cups while the other end fits the 8 internal splines of the crank arm adjustment cap plastic coated handle for a secure and comfortable grip warning this tool has a long handle and it is possible to damage the tool or the component by overtightening during installa