CooSpo Bicycle Speed And Cadence Dual Sensor Bluetooth 5.0 ANT+ Wireless Waterproof For Wahoo Zwif Garmin etrex 30x. There are 2 kinds of light display, if the speed sensor is installed correctly and the wheel is rotated, the LED indicator will flash blue; if the cadence sensor is installed correctly and the crank is rotated, the LED indicator will flash green.
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