When SRAM found ways to make their lightest and stiffest crank even lighter, they went for it. A new optimized layup drops 29g from the hollow carbon arms. The X-Range gearing technology minimizes cadence changes during front shifts, maximizing your ability to put power down. Plus they&';re offering more crankarm lengths than ever before to ensure this crank works for you. One-piece 2x chainring results in a lighter weight, stiffer, more durable crankset 29g lighter than the previous generation X-Range gearing technology gives you more range and a smoother gear progression, so you re always in the right gear Designed to deliver crisp and accurate front shifts Ultra-light hollow carbon fiber crankarms DUB bottom bracket adds durability and simplicity (DUB bottom bracket sold separately) Can be upgraded to a power meter set up (Power Meter chainring sold separately) 45mm Chainline