U.S. Engineer Soldiers Train on the Construction of a Pontoon Bridge

U.S. engineer soldiers train on the construction of a pontoon bridge. These men are all wearing the wool trousers and shirt with field jackets. The man in the centre is wearing the first pattern "Olive Drab Field Jacket", commonly known as the M1941. This jacket differed from the later, and more common, M41 field jacket only at the pockets. Pockets on the M38 jacket featured a button closure flap over the pocket. This was eliminated from the M41 field jacket.

Source :
Book "Patton's Third Army" by Christopher J. Anderson