Used to remove and install external bearing crankset bottom brackets, Work with external bearing crankset bottom brackets, including: Shimano BB80B, Shimano BB80D, Shimano BB4600, Shimano XT BB70B, Shimano BB52B, and previous external bearing threaded cups, Fits many external threaded types for: Campagnolo, Fulcrum, Chris King, Hope, Surly, Wheels, and more, Fits bottom brackets with 16 external notches and an outside diameter of 44mm