I got an old Linhof Bi Kardan recently, and it had an oddball bellows. It looks like a combination bag bellows and regular bellows, since it has the features of both.
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I actually have another one that I got years ago, but that one is badly deteriorated and unsalvageable. This one seems to be O.K., so I'll probably use it.

My question is, what was this bellows intended for? I'm assuming it would be useful for short and standard focal length lenses, but maybe there was a special purpose. Should the bag portion be at the lens end or the back end?