Laser pistols detect speeders earlier than expected: range of up to one kilometer. Depending on the device, the speed can be recorded up to 1,000 meters in front of the actual speed camera.
If the speed is above 100 km/h, three percent is considered a tolerance range. With a speed limit of 100 km (h), that's three km/H. With the Riegl FG21-P, drivers can be transferred in up toOne kilometer, according to e-fahrer.de.