You Do Need power plug adapter while traveling from Swaziland to Guinea-Bissau.

Here is Why You Need An Adapter

The outlet and plug type used in Guinea-Bissau is C and in Swaziland is M. This is how they look like.

In Swaziland, outlets of type M are in use.

Type M

In Guinea-Bissau, outlets of type C are in use.

Type C

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