FEATURES * High precision gasoline engine RPM measurement, measurement just clamp the Inductive Pick Up sensor to the high tension wire. * Secondary tach. measuring method, no matter what cylinder is. * 4 cycle & 2 cycle select switch, available the automobile engine, motorcycle engine, generator engine... * 0.05% accuracy, high precision. * Wide measuring range from 10 to 50,000 RPM. * Separate inductive pick up sensor. * Memory the last value, max., value, min. value. * Used the exclusive one chip Micro-Computer LSI circuit, crystal time base. * Durable housing case.