The Oversized Pulley Wheel System for SRAM Red and Force AXS features a 15-tooth upper and 19-tooth lower pulley wheel setting, for maximum efficiency.The system offers a two spring tension setting that allows for optimal setup based on riding conditions.These hollow 3D printed oversize pulley wheels are 10% lighter than aluminium oversized pulleys.The innovative 3D printed technology provides the pulleys with a two times longer lifetime compared to the aluminium version.This product is an exclusive option designed for maximum strength and lower friction.The combination of 3D printed titanium oversized pulley wheels and coated CeramicSpeed Bearings result in the best pulley wheels in the world.Since the pulley wheels are the fastest spinning bearings on your bike, this CeramicSpeed upgrade is the most effective way to save energy or improve your time.Entirely developed, designed and produced in Denmark by CeramicSpeed, the Oversized Pulley Wheel System is a technologic advance for the cycling industry.Matching the highest quality materials with a unique design, the OSPW System delivers lower friction and longer lifetime, improving your competitive advantage.Coated bearings come with an extremely thin (2-3 microns) protective layer, which is 75% harder than hardened steel.This is applied to the entire raceway, and makes the bearing even more resistant to contamination, as well as further reducing friction.