The Heeres-Sturmartillerie crew Replenished their 75mm shells ammunition to their Sturmgeschütz III (StuG III) from a parked Sd.Kfz. 252 leichte Gepanzerte Munitionskraftwagen. Presumably Italian Front in 1943. The Sd. Kfz. 252 was based on the Sd.Kfz. 250 half-track and used the same chassis. Initially built by the Demag and Wegmann firms from June through to December 1940, production shifted to Deutsche Werke from January to September 1941. 413 vehicles were manufactured, all of which were issued as ammunition resupply vehicles to Sturmartillerie batteries and saw operation on both European fronts. This picture itself gives a good comparison between the dull grey paint as used on many German AFV's, and the field-grey uniforms which had a tinge of green
Source:
http://en.wikipedia.org/wiki/Sd.Kfz._252
http://histomil.com/viewtopic.php?f=338&p=100353