Review on LuTuo Wireless Cycling Speedometer - Waterproof Bike Speedometer - Bicycle Odometer with LCD Backlight - Automatic Wake-up & Multi-Functions Cycle Computer for Outdoor Sports MTB BMX - Men and Women by Malik Munns

Smart little gadget - just hold your computer battery over a white panel. There is a small O-ring in the battery compartment. You'll only know it's there when it falls out - and hopefully it's above the white plate. And yes, I'm still looking for it under my desk! In addition, the receiving nut on the computer mount is only held in place by the clamping screw. When opening the handlebar mount clip, be sure to keep your thumb on it - it's tiny and very easy to fall out and disappear. drop out too. For obvious reasons, be sure to mount the sensor with the battery compartment facing out.