You Do Need power plug adapter while traveling from Congo to Central African Republic.

Here is Why You Need An Adapter

The outlet and plug type used in Central African Republic are C and E and in Congo are C, D and E. This is how they look like.

Congo

In Congo, outlets of type C, D and E are in use.

Type C

Type D

Type E

Central African Republic

In Central African Republic, outlets of type C and E are in use.

Type C

Type E