The REED R5710 is a clamp-on earth ground resistance tester that measures ground resistance without needing auxiliary ground stakes, using auto-ranging scales down to 0.001-ohm resolution and covering roughly 0.01 to 1200 ohms. It also measures leakage current up to 20A, stores up to 300 readings in internal memory, and features a backlit display with programmable alarms and a durable double-molded clamp jaw (CAT III 300V rated). This listing is the NIST-certified version, supplied with a traceable calibration certificate along with the standard resistance calibration loop and hard case.