With the Extech 380396, measure insulation resistance to 60 GΩ with test voltages of 500 V, 1000 V, 2500 V, and 5000 V. It features several measurements including polarization index (PI), dielectric absorption ratio (DAR), and AC/DC voltage to 600 V with a min/max function. It also has peak and relative functions, as well as a 1 to 15 minute timer function for IR measurements. Comes with test leads, eight C batteries, 220 V AC adaptor, heavy duty carrying case, and user manual.