These cameras were produced by factory "KMZ" (Krasnogorsk) since 1954 up to 1955.
Frame size 24X36mm

Lenses: Jupiter-8 (2/50mm)
Lenses for Zorki-3M are here
Adjustable shutter speeds: 1sec, 1/2, 1/5, 1/10, 1/25, 1/50, 1/100, 1/250, 1/500, 1/1000 of a second and "B".

Basic difference from Zorki-3: There are one shutter head on the top