This tachometer can also be used to determine how fast motors and propellers are turning. Now you can more accurately tune and performance test your engine, motor, edf or heli with the Turnigy tachometer.
Everyone knows how much fun a fidget spinner is. Now you can measure the speed the fidget spinner is rotating using this excellent Turnigy Fidget Spinner Tachometer.
 
Measures 2 to 9 propellers.
Extremely easy to use.
0-99999rpm range