Program in the average speed to be achieved to one decimal place, and the Automatic Speed Table will display how far you should have travelled to two decimal places, in miles or kilometres, over the elapsed time period.A backlit display ensures readability at night and an audible tone indicates switching on or off. NEW- LARGE Buttons Internal ON/OFF Switch to avoid accidental power off s. 4 digit large LCD readout 4 mechanical push-switches to calibrate to any speed 0.1kph to 999.9 mph (either mph or kph) Solid state back-lighting Audible beep on or off by use of S button (see options) Speed to one decimal place Small (10cm long) pocket size caseAvailable in 2 optionA5 : Beeps at either 10m or 100m intervalsA9 : Beeps at 100m or 1km intervals1 x PP3 battery is required for operation