Good photograph. That Mercedes-Benz ACTROS 4051 Tractor AHSVS is one of 21 purchased in 2007 for service in Afghanistan. The flat-bed trailer I am not sure of the type although something I learned a while ago about CF vehicles is that they are easier to identify if you can capture the CFR number.
Attached is a photograph of a ACTROS 4051 Tractor AHSVS taken in Afghanistan.