Excellent product. Mount this small unit on the dash board of your bike ( Can be battery powered or wired into the bikes wiring loom ). Then whatever track you are at you make the first lap and press a button to store various split points and the startline. Once this is done the GPS tells you if you are on a fast lap and records each lap time brilliantly. After the session you can download the data to a laptop and it will give you a circuit diagram and your speed/time around the circuit. Laps can be compared. The unit also has a shift light. This is probably the best product that i have fitted to a bike. I found it best to wire the unit into the bikes wiring loom to obtain power as battery life is low.