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

Saudi Arabia

In Saudi Arabia, outlets of type G are in use.

Type G

Thailand

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

Type A

Type B

Type C

Type O