Kriegsmarine 7x50 binocular case 'Carl Zeiss Jena'

A nice original example of the storage case for the Kriegsmarine 7x50 binoculars - such as the gas ocular variants - as produced by Carl Zeiss Jena. 
 
This particular model is made from the typical black rubberised ersatz material and even still retains the original leather shoulder strap. Internally, the 4x sun filter holders are also still present and correct, as shown. 
 
The case is clearly marked 'Carl Zeiss Jena', along with the KM 'M IV/1' eagle proof, and notably stamped (as well as also lightly hand-inscribed) '1019' to the top of the lid... the significance of which is unknown, but clearly important enough to have been applied multiple times nonetheless! 
 
A scarcely seen accessory which would make the perfect addition to complete a pair of KM issue Zeiss 7x50 binoculars which are missing the storage case!