The GCM-403 is a digital clamp meter that can measure AC/DC voltage, AC/DC current, resistance, diodes, continuity, capacitance, frequency, and temperature. Tapered jaws, auto range, data hold, REL function, and auto power-off which makes it a superb tool for electricians. The GCM-407 is a digital clamp meter with true RMS measurement. Featuring tapered jaws, a wide range (AC 600A/750V, DC 1000V max input), capacitance measurement as well as non-contact voltage sensing function, and the ability to keep MAX/MIN or hold data and automatically power down make the GCM-407 suitable for almost any cable measurement task.