Premium Round chainring designed for Sram GXP? and BB30 Long spindle that feature a removable spider. Spiderless (direct mount) chainrings allow for flawless single speed or Sram 1x9/10/11 drivetrain setup. Size (Mass +/-1g):28T(49g), 30T(50g), 32T(52g), 34T(66g), 36T(72g). Color; Black, Racing Red, Green. Compatibility; SRAM XX1, X01, X0, X9, X7, S2210, S1400 and Truvativ AKA cranks. GXP? and Long spindle BB30 models. Compatible with Boost148 as well. Material; cnc machined 7075 Txxx Aluminum. Long-lasting construction. Finish. Anodized Chainline 50mm Tooth Shape Can be used with singlespeed, 1x9, 1x10 and 1x11 as it fits all chains. Tooth shape optimized for quiet work.These direct mount chainrings save more than 150g over the regular spider and chainring combo. Reliable, extremely light, stiff and clean looking on the bike. Fear no more about loose chainring bolts or compatibility issues ? go spiderless! This is currently the lightest solution on the bicycle market. This chainring is for GXP? and Long spindle BB30 crank model only. Always use a new chain with a new chainring. Optimized to ride in heavy mud thanks to specially designed chamfers. The most advanced, Patent Pending narrow-wide tooth profile on the Market guarantee minimum 12 months of excellent chain retention capabilities! We mean it. You can finally take your chainkeeper off of the bike. Tested by XC Silver World Champion Marek Konwa.