Maximum capacity 500 Watts. This voltage converter can be used in 110 volt countries and 220 volt countries. It will convert from 220-240 volts to 110-120 volts and vice versa. There are two outputs on the front of this unit, one for 110 Volts and one for 220 Volts. Both of these female outputs are universal and will accept 2 or 3 prong male plug adapters from anywhere in the world. There is an input voltage selector switch on the back of the unit which allows you to select from 110, 200, 220, and 240. Insulated power cord is hard wired with a grounded plug adapter for USA, Canada and Mexico. An additional European/Asian grounded "Schuko" plug which is good for European/Asian outlets is also included. Voltage Converter is used to convert the voltage of the source (coming from the wall) to match the voltage required to run the device. Voltage converter / transformer can be used to transform 110V coming from the source (wall) to 220/240V or 220/240V coming from the source to 110V. These power converters can be used overseas like Europe where the voltage is 220V to run 110 V devices or in US (where power is 110 v) to run overseas 220 / 240 volt devices. Voltage Converters are referred to as power converter, travel converter, voltage transformer, voltage convertor Europe, travel voltage converter, transformer voltage, volt transformer, AC power, travel voltage and voltage regulator. The travel converters are sometimes referred to small AC voltage converters which are used to run CD players etc. This voltage converter can be used continuously for extended period of time. Step Up Transformer is used to step up the source voltage (coming from the wall) to match the voltage to run the device. Vice versa with Step Down Transformer. All Voltage Converter/ Power transformers can be used continuously. We recommend adding 25% to your devices wattage to accommodate any kind of surge while selecting a voltage transformer/ converter.