CeramicSpeed Oversized Pulley Wheel System for SRAM Mechanical 10/11-Speed Derailleurs * Coated Bearings, Alloy Pulley, Carbon Cage, Black

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 two oversized 17-tooth aluminum pulley wheels
Robust cage crafted from polyamide and carbon fiber for durability and light weight