All Oral-B toothbrushes come with region-specific battery chargers, so you will have to check the voltage and buy an adapter depending on the country you are visiting. For example, if you are traveling from the US to Europe and your charger is a US 110v, you can buy the Oral-B 220v charger, which can be used overseas without purchasing a voltage converter. The other option is to keep the US 110v and buy a voltage converter, and a plug adapter as plugs are different in European countries.