This is a WW2 German army heater. The use for it was to heat the battery and engine of a vehicle when it had trouble starting in the winter. The heater can work with either Diesel fuel or even Coleman stove fuel. These heaters were often used for other types of heating such as heating trenches and tents. This item is in excellent condition and would work again if fueled up. Clear German markings. Another unusual piece of WW2 German Army equipment.