Kiev 4a? Russian army Analogue camera

Very rare Kiev (model 4a but without certainty), originating from the Russian army, with various Cyrillic inscriptions and a red star on the front (above the number 2...), the symbol on the left side of the aircraft corresponds to the letter 'f', and on the back of the aircraft, there is the inscription:
The soldier is responsible for the equipment.

I don't know if it's a prototype or a commonly used device; what matters is that it was equipped with a Carl Zeiss Biotar 58cm f2 lens, which I couldn't find any mention of, and an old photography seller told me it was probably a prototype (I'm keeping the lens for now).

Like any self-respecting Kiev, the curtains are a bit tired, and time isn't necessarily respected.

Apart from that, everything works; the focus is a little stiff, and the patch in the viewfinder is perfectly visible.

A very beautiful piece for a collector.