Shimano FC-R8100 Ultegra Rear 12-Speed Hollowtech 50-34T Front Chainwheel

• Outer ring material: Aluminum/ CFRP
• Crank axle material: Steel
• Average weight: 700g,711g
• Threaded BB shell width: 68/70
• Crank arm finish: Anodized
• Compatible BB type: Outboard
• Crank axle finish: Plated
• Gear arms: 4
• Compatible chain: CN-M8100
• Inner ring material: Aluminum
• Inner ring finish: Anodized
• Crank arm length: 160,165,170,172.5,175
• Chain ring combination: 0-34,52-36
• Outer ring finish: Anodized
• Crank arm material: Aluminum