In addition to the 426 US6 U-5 delivered, and due to the lack of domestic chassis, the Red Army fitted the short-wheelbased U2 with self-produced 1,200gal. petrol tank bodies and called them BZ-35S, the "S" as the distinction to the domestic ZIS-6 tank truck.
The refuellers served successfully at the Red Airforce (»VVS«) as well as at the ground forces where they filled the gap between the railway and the ever advancing troops.