Bruso digital steering wheel

Hello everyone, anyone know this device? Its a digital rpm, speed, temp meter and timer. A friend got this from an old kart but neither of us know how it works, anyone of you know it or have a manual of it? I already know how to see the rpm, temp and speed, the timer just work manually, I don’t know if this magnetic probe is old or something like that but don’t take times on the track.
I appreciate any help!

Have a nice holidays.
César Oliveira