Magic Mirror Helicopter Optical Tachometer V2.0 RCD3063 RCD3063 mirror optical speedometer also called optical electronic shutter speed table, which is a kind of synchronous speed list, it is to use the human eye vision for a combination of high-tech electronic shutter effect of static object technology observation like apparatus, when electronic shutter and object to be tested in the same exercise frequency open and shut, users through the magic mirror speedometer point of window see of the static object to be tested, and at the time of the show is the actual speed rotating speed of the object. RPM measurement range: 800 - 20000RPM