SRAM AXS E1 Power Meter Spider For Threaded Mount Chainrings I Have The Powerrrrrrr! Power is an important metric when it comes to pacing yourself in a race or figuring out if you're improving during your training efforts. When you need the absolute best from your training data, the accuracy and reliability of the SRAM XPLR AXS Power Meter is the way to go. The spider design uses a proprietary thread-on chainring mount system, which allows SRAM to reduce weight and increase stiffness without compromising the ability to swap rings. A dual-sided power measurement system, it's accurate to +/-1. 5% even as weather conditions change, and boasts unbeatable battery life. Features Thread Mount design is light, stiff, and accurate User-replaceable CR2032 battery with 200-hour battery life Bluetooth low energy technology and ANT+ wireless data transfer Magic Zero automatically checks and recalibrates your power meter as you ride IPX7 waterproof to 1 meter for 30 minutes AXS-enabled for easy monitoring and firmware updates | Sram | Axs E1 Power Meter Spider For Threaded Mount Chainrings Force E1 | Aluminum