KM Area/district number??

[David H]

Hello,
I have seen a Mgz sight tin with a little metal plaque on it saying MG34 underneath that it says Nnr 453.
I remmeber reading somewhere these numbers related to Naval areas/commands is that true?? and if yes which does Nnr453 refer to??

Thanks
David

[compressore]

Machine gun 34 and weapon number to relate the sight to the weapon