DZero XX1 Eagle DUB Spider Quarq Dzero XX1 Boost power meter spider must be paired with a XX1 Eagle DUB 8-bolt crankset and a 104 BCD X-SYNC 2 chainring Not compatible with SRAM's 3-bolt direct mount interface Bluetooth low energy technology and ANT+ wireless data transfer MagicZero technology automatically checks and recalibrates your power meter as you ride – no need to manually calibrate AxCad system provides no-magnet cadence data OmniCal system allows you to swap chainrings without affecting accuracy Use the AXS app to easily update firmware and view power meter metrics Uses a CR2032 battery that can be replaced without tools Measures power for both legs with +/- 1.5% accuracy IPX7 waterproof rating