The Double Ended Bottom Bracket Wrench features a tool at either end for 16-notch cups with a 44mm diameter on one side as well as a 16-notch, 48. 5mm diameter wrench on the other end. It's compatible with all current Wheels Manufacturing bottom brackets with notched cups as well as many other outboard bearing bottom brackets including Shimano, FSA MegaEXO, Campagnolo Ultra Torque, and SRAM/Truvativ.