You Do Need power plug adapter while traveling from Benin to Chad.

Here is Why You Need An Adapter

The outlet and plug type used in Chad are C, D, E and F and in Benin are C and E. This is how they look like.

Benin

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

Type C

Type E

Chad

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

Type C

Type D

Type E

Type F