I have a few questions concerning WWII Russian mortar rounds. Any help will be greatly appreciated.

1: When was the MП K (MP K) fuse accepted into service? Was it used on the 50mm or the 82mm?

2: What is the difference between The GVM and the GVMZ fuse?
3: What was designation for the fuse for the 82mm propaganda/leaflet round?

4: Can anyone identify this 82mm? It was listed on an auction site an Os 832 round. As far as I know there is no Os 832. It looks like a propaganda/leaflet round but it is different than the A-832. What fuse is on this?

Thank you
Dan

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