For Namibia the records list Types C, M and N at 230 V and 50 Hz. At 230 V the supply matches what UK and European appliances expect, so no converter is needed.
Handy for multi-stop trips: South Africa and Eswatini use the same plug types. Nearby but different: Uganda, the Seychelles and Nigeria – an adapter for Namibia will not fit there. 3 of the 55 destinations in Africa share the plug types of Namibia.
Protective earth
Grounded and ungrounded sockets may occur
Mixed supply: Type C without earth, Types M and N with earth. Which one is in your room only shows on arrival.