Klein Tools 400A Clamp Meters are automatically ranging digital clamp-meters. The meters measure AC current and non-contact voltage tester (NCVT) via the clamp and AC-DC voltage, resistance, and continuity with test-leads. The meters feature the NCVT integrated into the clamp jaw and test leads with CAT III/VI safety caps. The units have a CAT III 600V, Class 2, double insulation safety rating. Klein Tools 400A Clamp Meters meet the requirements for use in basic and controlled electromagnetic environments, including residential, office, and light-industrial locations.