Kogel Bearings 14/18T Hybrid Ceramic Pulley Set Transmission BlackExperience silky smooth pedaling, improved shifting accuracy, and extended durability with Kogel ceramic derailleur pulleys designed for the latest SRAM Eagle Transmission The pulleys are equipped with aluminum cogs and serviceable bearings that resist the most challenging mountain bike conditions The 14T upper and 18T lower pulley wheels maximize the tooth count to reduce friction Cross seal are built for leaving the beaten path, offering the best