• EXTERNAL BOTTOM BRACKET TOOL. • FOR USE WITH OUR 32MM CNC ROD, AN ADJUSTABLE WRENCH OR 3/8 SOCKET DRIVE.• EXTERNAL BB TOOL• 16 NOTCH, 41MM• SHIMANO 105 BBR60, ULTEGRA 6800,XT MT800, SHIMANO CRANK DUST CAP TOOL, 16MM HEX