You Do Need power plug adapter while traveling from Dominican Republic to Cayman Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Cayman Islands are A and B and in Dominican Republic are A, B and C. This is how they look like.

Dominican Republic

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

Type A

Type B

Type C

Cayman Islands

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

Type A

Type B