The SRAM Force carbon 2x crankset is the very center of the X-Range gearing philosophy. With tight 13-tooth gaps between chainrings paired to wide-range cassettes, riders get more range while shifting less frequently and staying in the big ring longer X-Range gearing technology gives you more range and a smoother gear progression, so you&';re always in the right gear Crisp and accurate front shifts Carbon fiber crankarms for light weight and stiffness Unique chainring shape results in a lighter weight, stiffer, more durable crankset DUB bottom bracket (Sold separately) adds durability and simplicity Can be upgraded to a power meter 45mm Chainline Crank Intended Use: Road, Gravel Pedal Spindle: 9/16" Chainline/Hub Compatibility: 135/142 Road Disc Hubs < 415 mm Chainstay, 141/148 Boost Hubs Rings: choose; 43/30T, 46/33T, 48/35T, or 50/37T Spindle Interface Type: SRAM DUB Drivetrain Speeds: 12 Chainring BCD: Direct Mount SRAM BB Included: No Color: Iridescent Gray