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 a 14-tooth upper pulley wheel and a 18-tooth lower pulley wheel to provide absolute optimization of the rear derailleur The narrow wide tooth profile ensures durable chain retention Robust cage is crafted from carbon reinforced polyamide for durability and light weight Three spring tension settings allow you to customize performance and reduce chain drag Offers up to 40% efficiency savings, compared to the stock SRAM Eagle cage Fits 10-50 tooth cassette range Specs: Fits BrandSRAM Drivetrain Speeds12 Defined ColorBlack Fits ModelXX1 Eagle AXS Fits ModelX01 Eagle AXS Largest Cog50