The MT-14, a self-powered Digital Tach/Maintenance/Hour meter, keeps track of true engine RPM and running time for all types of gasoline engines. The unit is powered by an internal lithium battery. No external power connections are required. The operation of the Tach/Hour meter is triggered by 1.67m (5.5 feet) shielded and external lead, wrapped around the spark plug wire of the engine. When the engine is running, the display will indicate RPM. When the engine is off, the total accumulated run time is displayed. This is useful for maintenance and warranty applications for any type of engine-powered machinery. This unit is built for maximum durability for harsh environments and rugged applications.