Extech 382357 Clamp-on Ground Resistance Tester Non-contact measurements of ground conductors without need for auxiliary ground spikes Auto ranging ground resistance measurements from 0.025 Ohm to 1500 Ohm with 0.002 Ohm resolution True RMS AC Leakage current range of 0.2mA to 30A with 1.000mA resolution Programmable Datalogging with 116 data points Programmable Hi/Lo Alarm