First you must ensure that the bottom bracket bearing size is compatible with your crank’s spindle diameter. If you have eeWings, then any of our 30mm bottom brackets will work with the 30mm spindle of the eeWings crank. If you have a SRAM DUB crank, then any of our 29mm (DUB) bottom brackets will work with the 29mm spindle DUB cranks. For shimano cranks, choose the 24mm option.