Supply SIMCO electrostatic field tester the FMX-003FMX-003 can be measured in the range + / -20 kV. Equipped with 2 LED lights to ensure the distance measurement in the standard 25mm shell of a conductive material, and a grounding buttons to ensure accurate and reliable measurement results. displayed numerically and graphically clear in a dark environment, but also a bright panel display lighting with ion balance measurement board, measuring the ion generator residual voltage measurement range of + /-200V.? Field measurement range + / - 20kV? 2 LEDs, 25mm working distance? measured with ion balance board (+ /-200V)? Click Reset to zero? click Display Lock? automatic shutdown of idle? battery performance? panel display lights