Technically, they're not milliseconds. Milliseconds would in fact go to 999 on the second counter. They're more like centiseconds. See below for an explanation: 1 metre = 100 centimetres, 1 metre = 1000 millimetres. Therefore, to follow the same logical process: 1 second = 100 centiseconds, 1 second = 1000 milliseconds. Therefore: Centi = 1/100, Milli = 1/1000 Since the numbers go to 99 before changing to a second, they should therefore be centiseconds.