If the non-heating appliances you travel with operate on 220-250 volts, and use up to 90 watts (many stereos, printers, monitors, medical equipment, etc.), you will need one of these transformers to operate them on North American 110 volt current. (An adapter plug may be needed; our Travel Gear Specialists can help you determine your needs.) (14 x 8 x 7.5cm; 1.36kg)