The AT Series tachometer is a rugged instrument with solid-state circuitry for indication of engine RPM.
It is equipped with a ring nut for mounting into a standard 3-3/8 in. (86 mm) dash mounting hole. A full 240° sweep of the pointer gives an accurate indication on a large easy–to–read scale, and the dial can be illuminated for night reading. The ATH Series model is also equipped with hourmeter to record the elapsed running time of an engine.