Replace your worn out SRAM Red pulleys or upgrade your 10 or 11-speed SRAM road rear derailleur to smooth spinning jockey wheels with the Road AeroGlide Ceramic Pulley Wheel Assembly Kit. As we've experienced with ceramic bearings in hubs and bottom brackets, its application in pulley wheels also promises reduced friction, increased stiffness, decreased weight, and added durability. The bearings come packed with a ceramic optimized grease that further lowers friction and adds longevity and each kit comes with an extra 10mL syringe of grease for maintenance.