A 6-volt transformer is an electrical transformer that is used to step up or down the voltage of electricity from a different source with a different voltage through magnetic induction. These transformers are commonly used to produce 6-volt power from 120-volt household current or the 12-volt current of car batteries.
Many small appliances and electronics use 6-volt power, particularly since this amount of voltage is available from common batteries. However, direct use of a higher-voltage current from a household circuit or car electrical system would likely damage such devices. A 6-volt transformer reduces the voltage of the input current and allows 6-volt devices to use these power sources safely.