Review on AGPtek® Professional Digital Tachometer Contact by Niko Knight

Unbeatable for the price. It is easy to use and provides accurate readings. It loses a star for the inherent pain in the applied part of its functionality. Because it works by reflecting off a piece of reflective tape that you stick on the rotating element, the reflective rotating element causes reading problems. Since most waves etc. are shiny, this can cause reading problems. A piece of black insulating tape can be glued to the shaft. or hold the device very, very still until the reading stabilizes. But if you need to read the RPM of something, this is a good deal.