ULTEGRA Crankset FC-R8000 SM-BBR60 • Chainring teeth combinations: 46-36T/50-34T/52-36T/53-39T • Bolt circle diameter: 110 mm ITEM SHIMANO DESCRIPTION NO. CODE NO. 1 Y1P417000 Crank Arm Fixing Screw Y1W898050 Left Hand Crank Arm Unit 165 mm Y1W898060 Left Hand Crank Arm Uni...