SRAM XX1 Eagle DUB Power Meter Power Meter Crankset Speed: 11/12 Spindle: 28.99mm BCD: 104 32 DUB 170mm Black BoostBluetooth low energy technology and ANT+ wireless data transfer MagicZero automatically checks and recalibrates your power meter as you ride no need to manually calibrate AxCad no cadence magnet required 10K Temperature Compensation Battery CR2032, 200 hour battery life, change without tools OmniCal swap chainrings without affecting accuracy 2 year warranty IPX7 waterproof rating Accuracy within 1. 5%, measuring both legs. SRAM Model ID: PM XX 1 C1