Quarq: Every innovation in Quarq’s DZero platform represented the 10+ years of Quarq’s advances in power meter technology. This same platform is now combined with SRAM’s innovative DUB technology to bring you the simplest spider-based power meter. Simplified part choices, quality materials and a broader compatibility for bottom brackets and chainrings, brings power on every ride.FEATURESBluetooth low energy technology and ANT+ wireless data transferMagicZero - automatically checks and recalibrates your power meter as you ride – no need to manually calibrateAxCad -- no cadence magnet required10K Temperature CompensationBattery -- CR2032, 200-hour battery life, change without toolsOmniCal -- swap chainrings without affecting accuracy2-year warrantyIPX7 waterproof ratingAccuracy -- within 1.5%, measuring both legs. SPECIFICATIONSSpeeds: 11/12Crank arm length: n/aBB Compatibility: DUB:BSA73, PF89.5, PF92, PF30 MTB73, BB30 MTB73, BSA MTB68SPChainring Size: No ringsBolt Circle Diameter (BCD): 104 BCDChainline: n/aBB Spindle Interface: DUBChainring material: No ringsGuard: No GuardCrank arm material: n/aColor (Crank arm): n/aPower Meter Type: ANT+ and BLE