Electric meters; electric testers, namely, circuit testers, electrical outlet testers; magnetic meters and testers, namely, magnetometers; recorders for measurement, namely, electronic data recorders; digital recorders for electric or magnetic meters and testers, namely, digital data recorders; data processing equipment, namely, data processors; data processing equipment for measurement, namely, data processors; multipoint recorders for electric or magnetic meters and testers, namely, electri...