Fantastic original 2cm FLAK muzzle cover made of gray canvas material (it looks blue, but trust me, its panzer gray). Marked with the maker code emj and a nice waffen amt. It is in very good condition, not pristine, but it looks like it has minor storage wear. This was designed to be installed not only to keep dirt of out the barrel, but also to provide a tail reflector for towing. A sort of FLAK fanny flag, perhaps equally useful on your next trip to the hardware store if you need to buy one really long pipe. It does appear these were used on all 2cm's, even the ones which would not have been towed.
This is an extremely rare item, the only pictures I was able to scrounge up during research have all been original, I couldn't find even a single image other than period shots. I feel like I have seen one before, but I believe that was in a book. I have paid nearly as much for an 8cm mortar muzzle cover in similar condition and those are actually not all that hard to find. Muzzle covers were frequently lost or destroyed. This one looks like it only survived because it was likely in a depot or a similar situation. Inside, I can just make out a bit of red grease pencil which was typically used in the manufacturing of canvas items, either to number pieces for assembly or for alignment of parts. These markings tend to wear off quickly when used, so it tells me this probably hasn't been used a great deal.
I love the standard German glass PTR 765 reflector on the back. It's just fun. It's certainly one of those pieces that really crowns a nice display. As silly as it might seem, it's items like this that often draw the most interest from the general public. People wont notice your site or boxes but they will see that reflector and say "oh neat, there was even a cute little reflector for towing, typical German over-engineering." Unfortunately for me, I do not currently own a 2cm, because I would absolutely keep it if I did. It is a prime example.
A note on "blue" canvas. I did a deep dive on trying to replicate the color of this canvas many years ago and after considerable experimentation the solution ended up being very simple. It is not blue, and there is basically no blue in it. The many facets of the fabric bring out the blueness which is normally not present in standard panzer gray. Its not a bluer version of panzer gray, if you put standard panzer gray on cloth, you get this blue color. It's not Luftwaffe, it was standard canvas for everyone.