You Do Need power plug adapter while traveling from French Guiana to United Kingdom (UK).

Here is Why You Need An Adapter

The outlet and plug type used in United Kingdom (UK) is G and in French Guiana are C, D and E. This is how they look like.

In French Guiana, outlets of type C, D and E are in use.

Type C

Type D

Type E

In United Kingdom (UK), outlets of type G are in use.

Type G

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