12 Man Zelts
The Zeltbahn was a very flexible use device. Each soldier was issued one Zelt pannel, 1 zelt rope, two zelt stakes, and one section of the pole. The Zelt could be worn as a poncho, made into a stretcher, used as a flotation device, and many other things. One soldier's Zelt could be combined with one or more other soldiers to create tents and other shelters.
An uncommon configuration for the Zelt is the 12-man walled setup. This provided much more headroom at the cost of a smaller footprint. This is typically seen with officers or headquarters type setups inside. It would be exceedingly difficult to fit 12 men into a space that has the exact same footprint as a standard 4 man pyramid. It stands to reason that this was constructed from zelt quarters that were not in use by soldiers on a daily basis. Perhaps command had access to a supply of these or they were collected from soldiers who were out of action for one reason or another. Another 12-panel configuration is essentially an elongated 8-man zelt. This has all of the benefits of the 8 man with even more useable floor space.