The portable, self-contained meter answers three basic questions: 1) Is static present and on what surfaces, materials or people? 2) How much static is present? 3) What is the polarity of the charge? To minimize error from extraneous static fields, the unit utilizes a recessed nickel-plated sensing electrode which operates on a high/low circuit. LO range is 0-3,000 volts and is read directly from meter; HI range is 0-30,000 volts and is 10 times the meter reading. For repetitive measurements, this instrument features a unique "quick zero" function which instantly re-zeroes the instrument and provides ground compensation for the user. Repeatability: ±1%. Accuracy: ±10%. Comes with 9V battery.