CeramicSpeed Oversized Pulley Wheel System (Black) (Shimano 9000/6700) (Ceramic Bearings)

CeramicSpeed OSPW System Description: The CeramicSpeed Oversized Pulley Wheel System provides optimization and increased efficiency of the rear derailleur through its extremely low-friction bearings and unique overall design. Features: Features two oversized 17-tooth aluminum pulley wheels with Grade 3 Silicon Nitride balls Robust cage crafted from polyamide and carbon fiber for durability and light weight Hardened steel bearing races Only compatible with Ultegra 6700/6770/6800/6870 mechanical and Di2 rear derailleurs and Dura Ace 7900/7970/9000/9070 mechanical and Di2 rear derailleurs (up to 28t cassettes) Not compatible with Shimano Dura-Ace 9100/9150 and Ultegra 8000 series rear derailleurs Specifications: Compatibility: Shimano Dura Ace 7900/7970/9000/9070, Ultegra 6700/6770/6800/6870 Speeds: 10/11 Speed Max Cog: 28T Color: Black