You Do Need power plug adapter while traveling from Malaysia 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 Malaysia is G. This is how they look like.

In Malaysia, outlets of type G are in use.

Type G

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

Type A

Type B

I am from

going to