You Do Need power plug adapter while traveling from American Samoa to Thailand.

Here is Why You Need An Adapter

The outlet and plug type used in Thailand are A, B, C and O and in American Samoa are A, B, F and I. This is how they look like.

American Samoa

In American Samoa, outlets of type A, B, F and I are in use.

Type A

Type B

Type F

Type I

Thailand

In Thailand, outlets of type A, B, C and O are in use.

Type A

Type B

Type C

Type O