This piece of equipment is the horse feed bag utilized by German cavalry and horse-drawn elements.  This one is an interesting story.  I acquired this item as an aside to the purchase of a pair of wartime era Soviet Telogreikas and one pair of matching trousers.  When the Soviet items were found by my German source, they were all stuffed inside this feedback.  This item has one 15 mm hole near the large opening end, a few small picks here and there,  and is a little faded.  Other than that, it is a solid specimen with all the drawstrings.  It is nicely marked for the L. Stromeyer & Co. of Konstanz, and dated 1935.