it is a basic unit, I have one. You just set how many laps for lane 1 and lane 2, and race. It will tell you haow many laps to go, if you beat the fastest lap time in that lane, it will breifly flash your new fastest lap, and at the end of the race it will report the fastest lap in each lane, with a flashing flag to indicate the winner.
It doesn't do anything else
cheers
Dave