The radical new look and feel of our X-SYNC(TM) 2 Eagle(TM) chainring is a direct result of SRAM drivetrain engineers studying the performance and wear characteristics of thousands of X-SYNC(TM) chainrings. We subjected every size of chainring to untold environmental and mechanical tortures, abuse and neglect, in both lab and real-world settings, to come up with a chainring that would augment the Eagle(TM) drivetrain&';s performance in all conditions. The longer, positive-rake tooth shape has been designed to work perfectly with the new Eagle(TM) chain to increase chain retention and overall pedaling efficiency, while decreasing friction, noise and wear. X-SYNC(TM) 2 chainring design increases chain retention, wear life, and reduces friction and noise. Designed to be used with Eagle(TM) chain SPECS COLORS: Black or Black/Gold MATERIAL: Forged and machined aluminum FINISH: Anodized COMPATIBILITY: Eagle(TM) or SRAM 11-speed DIMENSIONS: 148mm BOOST RATIOS: 30t, 32t, 34t SIZE/BCD: SRAM direct mount