You Do Need power plug adapter while traveling from Cocos (Keeling) Islands to Vietnam.

Here is Why You Need An Adapter

The outlet and plug type used in Vietnam are A, B and C and in Cocos (Keeling) Islands is I. This is how they look like.

In Cocos (Keeling) Islands, outlets of type I are in use.

Type I

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

Type A

Type B

Type C

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