We sell two types of voltage transformers, Step down Transformer and Step up Transformer. Step down transformers are used outside of the USA in 220240 volt countries and Step up transformers are for use in the USA. Or in other 110120 volt countries like Canada and Mexico. These models also offer a housing for the transformer so you will not feel the heat generated by the transformer. They also have multiple outlets 2-4 outlets depending on the model and an ONOFF switch for added convenience.