Zeiss 7x50 Kriegsmarine armoured U-boat binoculars 'blc'

An incredibly scarce pair of mid-war era Kriegsmarine 'smooth ocular' U-boat binoculars, still fitted with the very rarely seen original objective rubber armour and Bakelite Benutzer lens cover! 
 
Over the last 10+ years of focussing on optics, we have encountered just 4 (!) of these sets with the objective armour, specifically for use in the confines of a U-boat, still intact... 
 
They are very nicely and clearly inscribed with the Carl Zeiss Jena maker's code 'blc' and serial number. 
 
The coated lens optics still remain functional, but would also benefit from a clean / serivce if destined for any more serious usage purposes. 
 
A guaranteed full original, as found example that would make for a wonderful and unique display set within any KM and U-boat focussed collection!