It s the best of both worlds. A light and stiff direct mount chainring with accurate Quarq power measurement elegantly hidden inside the DUB spindle lets you stealthily gather the data you need to progress. So, you can focus your attention on the stunning finish of the carbon fibre crankarm.DUB-PWR spindle-based unit measures left side power to calculate total wattsLong battery life (400+ hours) to power a season of ridesUser replaceable AAA lithium batteryDUB bottom bracket adds durability and simplicityWaterproof (IPX7 waterproof to 1 meter for 30 mins)Lightweight (less than 40g heavier than standard crankset)Speed: 12BB Compatibility: All SRAM Road DUB BBsChainring Size: 40TCrank arm length: 165mm, 167.5mm, 170mm, 172.5mm, 175mm, 177.5mmChain line: 45.0mmBB Spindle Interface: DUBChainring material: AluminiumGuard: n/aBolt Circle Diameter (BCD): Direct Mount (DM)Crank arm material: CarbonColour (Crank arm): Unicorn Grey w/Laser FoilPower meter: YesPower Meter Type: Spindle