Nachrichtentruppen primarily used rigid backpack field telephone wire dispensers during World War 2. However, some folding backpacks were used. These folding backpacks were very simple in construction and had no means to evenly distribute wire on a spool during take up.
These folding backpacks are relatively rare today, but fortunately, after the war, the Polish copied the German design. These Polish copies are very reasonably priced and accept wartime German wire spools with slight modifications to the bearings.
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WW2 German Field Telephone Equipment 