Tantalus Monkey

Thanks for the help, I'm going to put it down as a Tantalus since I saw it in Cameroon

Hi NoamFossi! The Tantalus monkey was once considered a subspecies of the grivet (Chlorocebus aethiops). The grivet is now considered restricted to Ethiopia, Sudan, Djibouti and Eritrea, while the Tantalus monkey ranges from West to Central Africa. Some authorities consider this monkey and all of the members of the genus Chlorocebus to be a single species.
http://en.wikipedia.org/wiki/Grivet

I'm really not sure with this one, I was thinking it could be a grivet but the tantalus monkey looks just about the same.