You Do Need power plug adapter while traveling from Wales to Turks and Caicos Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Turks and Caicos Islands are A and B and in Wales is G. This is how they look like.

Wales

In Wales, outlets of type G are in use.

Type G

Turks and Caicos Islands

In Turks and Caicos Islands, outlets of type A and B are in use.

Type A

Type B