Shimano Dura-Ace BB-R9100 Hollowtech II Bottom Bracket

System engineering at its peak. Each of the components magnifies the qualities of the others for an unparalleled level of performance. Optimizing input to maximize output. That's how it achieves supremacy.

• Bottom bracket with small ball bearings for lightweight
• Advanced seal construction for smoother rotation
• English Thread (BSA) or Italian
• BB Shell Width: 68mm or 70mm
• Average Weight: 65g