AEMC 4620 KIT-500FT [2135.21] 4-Point Digital Ground Resistance Tester Kit with 500ft Leads for 4-Point Testing. The Digital Ground Resistance Tester Model 4620 performs earth ground resistance and soil resistivity tests. This direct reading tester measures from 0 to 2000Ω, and is auto-ranging, so it automatically seeks outs the optimum measurement range. The Model 4620 is rugged, easy-to-use and is ideal for maintenance crews performing numerous tests. It exceeds mechanical and safety specifications for shock, vibration and drop tests specified in IEC standards. It is designed to reject high levels of interference, so it can be used under difficult conditions such as high stray currents that normally affect accuracy. The Model 4620 is also available in complete Kits (150ft, 300ft and 500ft).