Ceramic Speed OSPW RS Alpha for Shimano The ultimate drivetrain upgrade The Ceramic Speed OSPW (Over-Sized Pulley Wheel) RS Alpha represents a refined, updated version of the legendary Ceramic Speed pulley wheel systems, designed to increase drivetrain performance and to add an element of customization to your high-tech drivetrain. This OSPW RS Alpha has a new updated, angular design that better complements the world of modern, high-performance road drivetrains. This design packs advanced features including Alpha pulley wheels with an Active Debris Remover that makes it virtually impossible for debris to get into the sealed bearing, even off-road. This design also acts to dynamically extract any debris off of the pulley as it rotates. The cage of the OSPW RS Alpha has been redesigned and reinforced to increase durability, while the composite pulley tooth profile reduces chain noise and increases wear life. Features Reduces drivetrain friction compared to stock derailleur cage/pulley Redesigned cage shape to complement modern drivetrains, and a new reinforced design for improved durability Composite tooth profile quiets chain noise and increases wear life Alpha Disc Pulleys with Active Debris Remover (ADR) virtually eliminates debris ingress into the bearing Lifetime warranty through Ceramic Speed for added peace-of-mind Customizable spring tension for an optimal drivetrain setup Team Edition available with an oversized Ceramic Speed logo, the OSPW that supported teams use Specifications Net Weight102 grams Pulley Material Aluminium Derailleur Compatibility Shimano Dura Ace RD-9250 and Shimano Ultegra RD-8150 rear derailleurs Manufacturer Item Number(s)113490 (OSPW RS Alpha, Black), 113491 (OSPW RS Alpha, Team) | Ceramicspeed | Ceramic Speed Ospw Rs Alpha For Shimano Black