The module designed for measuring the ac voltage by connecting to the switch plug directly or the other kind of switch plug. It is suitable for measuring the AC voltage in many place, such as office, factory, laboratory, household and so on. Feature: Measuring accuracy: ±1.5%, ±2 word Measuring range: AC 80-300V Consume power: ≤1W (about every 1200 hours consume 1 kilowatt-hour) Application: The product can show the voltage of power by connecting to the plug of AC 110V/220V It is important for you to let the children away from the product Don"t use the product in a damp environment Package Includes: 1x Digital Voltmeter