BRT-040 30mm Cup – 30mm ID bearing cup for use with BRT-040 toolkit – This reciever cups is designed to mate into the BRT-040 Master Cup to receive 30mm ID BB bearings and can be flipped to be used as a guide for the same bearings during reinstallation. This cup is also compatibe with the BRT-003 cup that, when combined with BRT-040 29/30, expands the functionality of that tool to also work with 30mm BBs.