The Watt's Up meter measures all the aspects of how power is being transferred. It measures current Voltage, Amps, Wattage. It keeps track of total Watt Hours (Wh), Amp hours (Ah) peak Watts (Wp) and peak Amps (Ap). It also records minimum Volts (Vm). The LCD display measures Voltage, Amps, and Wattage in real time and cycles through the other measurements.