Don’t require power plug adapter while traveling from Vanuatu to Tonga.

Here's why you do not need an adapter

The outlet and plug type used in Tonga is I and in Vanuatu is I and they are compatible with each other.

Vanuatu

In Vanuatu, outlets of type I are in use.

Type I

Tonga

In Tonga, outlets of type I are in use.

Type I