Features and Benefits: Can be used as a contact as well as a non-contact tachometer; Four styles of contact adapter tips clip easily to the top of the phototach; Infrared technology makes the phototach accurate, convenient, and easy to use; Infrared beam not affected by ambient light; Non-contact design results in (zero) torque loss for true precision; Phototach is equipped with a laser pointer for accurate targeting. Reflective tape placed on a revolving object can be measured at distances from 2" to 20". Wide measuring range and high resolution, 2.5 to 99,999 rpm with a large 5 digit display, autoranging, min./max. memory storage, and low battery indicator.