SRAM X-Sync Road Direct Mount Chainrings for RED and Force drivetrains feature a wide-tooth, narrow-tooth design to provides maximum chain control. SRAM X-SYNC wide-tooth, narrow-tooth chainring technology provides maximum chain control Laser-etched chainring finish is more durable X-Range gearing technology gives you more range and a smoother gear progression, so you&';re always in the right gear Details: Round or Oval: Round Direct Mount Type: Direct Mount SRAM Tooth Count: 40 Material: Aluminum Ring Position/Type: Chain Retaining Single Ring Drivetrain Speeds: 12 Defined Color: Gray