You Do Need power plug adapter while traveling from Great Britain to São Tomé and Príncipe.

Here is Why You Need An Adapter

The outlet and plug type used in São Tomé and Príncipe are C and F and in Great Britain is G. This is how they look like.

In Great Britain, outlets of type G are in use.

Type G

In São Tomé and Príncipe, outlets of type C and F are in use.

Type C

Type F

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