MULTIPLE MEASUREMENT FUNCTIONS: This power energy meter can measure and display voltage, current, energy, frequency, power factor, maximum current & power, time days cost and total kWh. Energy monitor plug with 7 modes for your choice. NOTE: The "day" and "time" are only counted for device with power larger than 0.5 watt. (Will not count time when device in standby mode). A great home assistant for energy saving and energy monitoring and bill saving.