Details
You do require a Smart Phone, which is up to date in the last few years to run the app that connects to the unit.
Simply strap the unit to the end of the barrel, open the app and start recording the speed of your shots.
The app records speed, custom profiles, calibres and gives multiple readouts depending on what you require. Store and save your data, or export it to use in other programs. The App can call out the numbers as you shoot, so no need to take your eye off your target.
No external light sources are required, night or day. Its not rated water proof.