SRAM XX1 11sp ChainsetDeveloped for maximum chain control, each tooth’s thickness is precisely CNC-machined to support the chain’s inner and outer links perfectly. X-SYNC Direct Mount chainrings let you tune your gear range to match your terrain, wheel size and riding style Features:Arm Material: Carbon arms with forged aluminium spiderRings: CNC machined ringsWeight: 645g (GXP BB, 175mm, 32-tooth ring)Technologies:X-Sync™: SRAM X-SYNC™ 1X chainrings provide the highest level of performance and durability. The SRAM X-SYNC™ tall square teeth edges engage the chain earlier than traditional triangle shaped teeth. The sharp and narrow tooth profile, as well as rounded chamfer edges helps to manage a deflected chain. To provide the best possible performance in muddy conditions, the X-SYNC™ chainrings have been designed with mud-clearing recesses for the inner chain links and rollers. Engineered in Germany, X-SYNC™ rings are an integral part of the SRAM 1X™ drivetrain Boost: With revolutionary advancements in bicycle componentry, like SRAM’s XX1, X01 and X1 drivetrains, mountain bike designers have been given almost limitless freedom to focus solely on the performance of the bike. Each advancement demands that the entire package works flawlessly. Aggressive Trail and Enduro riders have been increasingly enjoying the benefits of larger wheels, but many still view 27 5" and 29" wheels as a possible weak link. This is why SRAM has developed an open standard with Boost compatible components for SRAM drivetrain, hubs and RockShox forks Buy SRAM Components from Chain Reaction Cycles, the World's Largest Online Bike Store.