The Electronic Specialties True RMS Low Current Clamp Meter, No. 688, features a 3/4" clamp opening, which allows clamping over heavy duty ground cables and some multiple ground cable systems. The larger clamp will permit a wider range of use across heavy duty vehicles. This clamp meter has improved the drift on DC amps readings, and it has a built-in, full-range digital multimeter for true RMS accuracy. The clamp meter measures DC/AC volts, ohms, frequency, capacitance, diodes, continuity and temperature in Fahrenheit and Celsius. Multimeter test leads, a temperature probe and a zippered carrying case are included.