Apple Power Supplies: Changing voltage settings

Learn about the power supplies in various Apple products and whether they can switch automatically to voltages in other countries. Some Apple computers have an auto-switching power supply which monitors the incoming voltage and automatically switches itself accordingly. Other Apple computers have a power supply that must be manually switched for various incoming voltages. In this case, the change is made by moving the voltage selector switch which is accessible from outside the computer's case. Still other Apple computers have a power supply that is rated only for the country in which it is sold and it cannot switch to other voltages. The table below shows what type of power supply is in various recent Macintosh models. Some models can use the World Travel Adapter Kit. If your computer cannot use the World Travel Adapter Kit and you need a power adapter or power cord with an appropriate plug, contact an Apple-Authorized Service Provider (AASP) in the region.

Source: Apple - Support - Most Recent - iPhone