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 13-tooth upper and 19-tooth lower, Cerakote coated aluminum pulley wheels with Grade 3 Silicon Nitride ballsRobust cage crafted from polyamide and carbon fiber for durability and light weightCoated bearing races increase bearing service life by increasing hardness of race and reducing corrosionFour spring tension settings allow customized setup based on ride conditions Only compatible with the 2X-specific GRX 810, GRX 815, as well as the RX800, and RX805 derailleursCassette compatibility up to 11-36tCeramicSpeed products with coated bearings include a lifetime warrantyItem SpecificationsDefined ColorBlackDrivetrain Speeds11Fits BrandShimanoFits ModelGRX 810Fits ModelGRX 815Fits ModelUltegra RX 800Fits ModelUltegra RX 805keyword searchOSPWSLargest Cog36 CeramicSpeed OSPW X System for Shimano GRX/RX 2x11 Cage Assembly EAN: 5711050081820