You Do Need power plug adapter while traveling from Palestine to Liechtenstein.

Here is Why You Need An Adapter

The outlet and plug type used in Liechtenstein are C and J and in Palestine are C and H. This is how they look like.

Palestine

In Palestine, outlets of type C and H are in use.

Type C

Type H

Liechtenstein

In Liechtenstein, outlets of type C and J are in use.

Type C

Type J