SRAM's X-SYNC 2 Eagle chainring is a direct result of SRAM drivetrain engineers studying the performance and wear characteristics of thousands of X-SYNC chainrings. They 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 drivetrain's performance in all conditions. The longer, positive-rake tooth shape has been designed to work perfectly with the new Eagle chain to increase chain retention and overall pedaling efficiency, while decreasing friction, noise and wear.