A tachometer is located on the dashboard of the vehicle, behind the steering wheel. This tachometer is installed in the vehicle to measure and display the rotation speed of the disk or shaft. The tachometer displays the RPM (revolutions per minute), using a calibrated analogue dial. This dial is specially designed to adjust on the left side of the speedometer. In newer models the analog meter is replaced with a digital meter, as the vehicles offer an electric system. A tachometer is specially helpful in vehicles that offer a manual gear system. As they can signal the driver when the speed is too high or low for the gear they are driving on. This meter helps ensure that a lot of pressure is not being put on the engine, by running is on a low or high gear. This small in size tachometer, does a perfect job of displaying the amount of stress that is being laid on the vehicle. The tachometer can help keep the vehicle in shape while running, and keep the driver informed on the matter.