Whether you are traveling to or from the US, which uses 110V, to any country that uses 220V power, you can use this adapter for your small appliances. Dual channel voltage converter from 110V/120V up to 220V/240V and also from 220V/240V down to 110V/120V. Works with devices up to 80 Watts, such as hair driers, irons, or coffee makers. Has AC117V --- AC230V switch, Power indicator light and Surge protection. Compact and ideal for travel. You may require additional prong adapters. Here is how to use it: 1. Check your appliance's label or manual to make sure it does not require more than 80 watts of power. This adapter can only be used with devices of 80 watts or less. The device should also be compatible with both 50Hz and 60Hz frequencies, otherwise it may malfunction. 2. Next, set the switch on the back of the adapter. --- If your appliance was intended for use with 110V outlets (US style), then push the switch to the side that says AC117V. For example, if you have a hair dryer that was made for US outlets, but you want to use it in Europe, you would set the switch to AC117V. --- If your appliance was made for 220V outlets, you should set the switch to AC230V. Then you can use the device with US-style 110V outlets. 3. Plug your appliance into the adapter, and lastly, plug the adapter into the wall outlet. You may need a separate prong adapter for different outlet styles. Please do not use the adapter for long periods of time, it is intended for short-duration uses.