You Do Need power plug adapter while traveling from South Africa to Puerto Rico.

Here is Why You Need An Adapter

The outlet and plug type used in Puerto Rico are A and B and in South Africa are C, M and N. This is how they look like.

South Africa

In South Africa, outlets of type C, M and N are in use.

Type C

Type M

Type N

Puerto Rico

In Puerto Rico, outlets of type A and B are in use.

Type A

Type B