The Extech 4-Wire Earth Ground Resistance Tester measures ground resistance using the 4-wire method for accurate measurements in four ranges: 2Ω, 20Ω, 200Ω, and 2000Ω. Features include autoranging, automatic I (current) spike check, automatic P (potential) spike check, and Test Hold function for easy operation.

Additional features include automatic zero adjustment, AC earth voltage measurement, data hold, and auto power off. The large dual line LCD provides clear readings, and overrange and low battery indication ensure reliable operation. The tester is CAT IV 300V rated and comes with alligator clips, four auxiliary earth bars, hard carrying case, and eight AA batteries.