Allows you to use 100-120 volts equipment in a 220-240 volt country. This item will allow you to use 110 volts appliances in Europe, Asia, Middle East and all other 220-240 volt countries. This item is to be used on heating products from 0-1600 watts such as a hair dryer. Please remember that the 1600 watts does not mean you can use it on any 1600 watts appliance. It is only for small appliances that heat up.