You Do Need power plug adapter while traveling from Eritrea 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 Eritrea are C and L. This is how they look like.

In Eritrea, outlets of type C and L are in use.

Type C

Type L

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

Type C

Type F

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