Resistivity meter, MRU-200-GPS is the only meter in the market which uses all measurement methods. Possible measurements: earth resistance measurment with 2-pole, 3-pole,4-pole method, impulse earth impedance measurement, three kinds of measuring impulse 410μs, 820μs, 10350μs, earth resistance measurement without disconnecting measured earths (using clamp), GPS coordinates of the measurement are stored in meter memory.