Attributes . 3- and 4-pole Fall-of-Potential, earth resistance loop testing; 4-pole Soil Resistivity testing; Selective earth ground rod testing using 1 clamp; Stakeless earth ground rod testing using 2 clamps; IP56 rated for outdoor use; Rugged carrying case; USB data storage and transfer; Automatic Frequency Control (AFC) - identifies existing interference and chooses a measurement frequency to minimize its effect, providing more accurate earth ground value; R* measurement ? calculates earth ground impedance at 55 Hz to more accurately reflect the earth ground resistance that a fault-to earth ground would see; Adjustable limits - for quicker testing. Includes: GEO Earth Ground Tester; User's Manual; Batteries; Quick Reference Guide, and USB Cable . Names