ROCKBROS Cycling GPS Speedometer – IPX6 Waterproof, Wireless Bike Computer With Speed Sensor – 5.5cm X 5.9cm, 56g

This is the ROCKBROS bike computer—small, lightweight, and actually useful.

It uses GPS to track your speed, so no wheel sensors to mess with.

The shell is ABS, black, and IPX6 waterproof, so rain won't kill it mid-ride.

Screen's in English, interface is simple.

Powered by batteries, weighs next to nothing at 56g.

Model number 29210017001.

Great for road cycling or MTB.

Comes with a 1-year warranty.

If you're tracking mileage, speed, or just like seeing your stats, this thing does the job without clutter.

Made in China, but solid build for the price.