Here's a very nice Bontrager Trip 100 bike computer.  The battery is installed and the display shows.  Included but not shown is a magnet.

Feature Include

1. Analog wireless signal with 70cm range
2. Current, average, and maximum speed
3. Trip distance and programmable odometer with 10 hour rollover
4. Clock (12/24-hour) and total ride time with pacer
5. Auto start/stop, calories burned, and quickview clock
6. Multi-language interface (DE, EN, ES, FR)
7. Includes batteries, universal mount, sensor, strap, and magnet
8. Computer uses CR2032 battery, sensor uses A23 battery