Carnet du Passage

[JazzyPerry]

Its always the safest option.
But here is some more info that I got from Wikipedia:

In certain African countries, the CPD is not officially required, but is often used to facilitate temporary importation of a vehicle. Countries where the CPD may be used include: Benin, Botswana, Burkina Faso, Cameroon, Central African Republic, Chad, Comoros, Côte d'Ivoire, Congo, Egypt, Gabon, Ghana, Guinea-Bissau, Kenya, Lesotho, Libya, Madagascar, Malawi, Mali, Mauritania, Namibia, Niger, Senegal, Somalia, South Africa, Swaziland, Tanzania, Togo, Uganda, and Zimbabwe.
2010 Senegal Does not use the Carnet de Passage anymore.

http://en.wikipedia.org/wiki/Carnet_de_Passage