You Do Need power plug adapter while traveling from Sri Lanka to Sint Eustatius.

Here is Why You Need An Adapter

The outlet and plug type used in Sint Eustatius are A, B, C and F and in Sri Lanka is G. This is how they look like.

Sri Lanka

In Sri Lanka, outlets of type G are in use.

Type G

Sint Eustatius

In Sint Eustatius, outlets of type A, B, C and F are in use.

Type A

Type B

Type C

Type F