Don’t require power plug adapter while traveling from Guam to Costa Rica.

Here's why you do not need an adapter

The outlet and plug type used in Costa Rica are A and B and in Guam are A and B and they are compatible with each other.

Guam

In Guam, outlets of type A and B are in use.

Type A

Type B

Costa Rica

In Costa Rica, outlets of type A and B are in use.

Type A

Type B