The Deumo MT-500 Mechanical Hand-Held Tachometer, Complete Kit - DEUMO 2 (Feet/Min version) is a precision instrument that accurately measures rotational and surface speed. The MT Mechanical tachometer rugged construction and portability make It an ideal choice for maintenance personnel, machine operators or others in a wide variety of machinery and material handling applications. This analog tachometer does not require batteries which makes it a perfect tool for field service personnel.