Sram Red AXS XPLR power meter spider is design for use with their 8 bolt direct mount and thread on chainring systemProprietary thread-on chainring mount system which allows us to reduce weight and increase stiffness without compromising the ability to swap ringsMagicZero automatically checks and recalibrates your power meter as you rideBluetooth low energy technology and ANT+ wireless data transferUser replaceable CR2032 battery with 200-hour battery lifeWaterproof (IPX7 waterproof to 1 meter for 30 minutes)AXS enabled for easy monitoring and firmware upgradesNo cadence magnet requiredDirect mount - DUBThread OnBlackUPC/EAN/GTIN: 710845904783