The Halda Speedpilot is a mechanical rally computer that helps the driver complete a ride exactly at the given average time. The Sports Special MK V is available in a miles/h and a km/h version. This Speedpilot is in km/h with a scale from 40 to 150 km/h. For rides that need to be driven at a lower speed, there is the "1/2 scal" setting, 20 to 75 km/h. How does something like that work? 1. Determine the average speed required to reach the final destination at the correct time. 2. Set the speedometer to the desired average speed. 3. Set the trip meter to 0. 4. At the start: place the pilot hand at the centre of the minutes hand. As long as you keep the average speed, the pilot hand and the minutes hand will be synchronous. When deviating from the desired average speed, the pilot and minutes hand will diverge. You can then read the deviation in parts of minutes and you will only have to adjust the speed until the hands are in the same position again in order to arrive on time. This Speedpilot is in a very good condition, externally as well as mechanically. All knobs and settings work properly. The clock runs and keeps time well. The screen is original and scratch-free. All knobs are original. The lighting works. Will be carefully packaged and sent by registered and insured shipping. -