The SRAM RED AXS power meter kit is used to upgrade your RED AXS crankset to a power meter. Kit includes chainrings. X-Range gearing technology gives you more range and a smoother gear progression, so you re always in the right gear Unique chainring shape results in a lighter weight, stiffer, more durable crankset Integrated chainring design significantly reduces weight AXS enabled for easy monitoring and firmware upgrades Power readings are accurate within +/-1.5% and aren t affected by climate conditions during a ride Power balance measures left and right legs separately SRAM X-SYNC wide-tooth, narrow-tooth chainring technology provides maximum chain control 8-bolt direct mount compatibility only to new RED eTap AXS cranks Chainline/Hub Compatibility 130 Hubs Chainline/Hub Compatibility 135/142 Road Disc Hubs < 415 mm Chainstay Chainring BCD Direct Mount SRAM Color Gray Defined Color Gray Direct Mount Type Direct Mount SRAM Drivetrain Speeds 12 Material Aluminum Material Aluminum Ring Position/Type Inner Round or Oval Round Tooth Count 48/35