See also:

Tachometer
The tachometer indicates engine speed in revolutions per minute (RPM). Do not rev the engine into the red zone 1 . When engine speed approaches the red zone, shift to a higher gear or red ...

Trailer brakes
If your trailer is equipped with a braking system, make sure it conforms to federal and/or local regulations and that it is properly installed. Never connect a trailer brake system directly ...

Speedometer
Speedometer The speedometer indicates vehicle speed in miles per hour (MPH) or kilometers per hour (km/h). ...