Amprobe TACH-20 Contact and Non-Contact Tachometer * Measures rotational and surface speed * Built-in memory * Digital display * Auto power off function * Easy to select units and mode functions * Contact and non-contact measurement * Select rpm using infrared beam or adapter: m/min, m/sec, ft/min, ft/sec, in/min, m, ft, and in. * Includes 6 adapters, carrying case, reflective tapes batteries and users manual