PK8200. "Rollei" style prototype camera, released by GOMZ in 1936. Conceived by B.A. Lebedev (original idea - "Icoflex" by Zeiss Ikon). Under name "START" in Cyrillic characters. The sample below has "GOMZ" logotype on the waist level's folding top and other markings in Cyrillic characters. The shutter "Moment" (Gomz) with speeds: 1s, 1/2s, 1/5s, 1/10s, 1/25s, 1/50s, 1/100s, 1/200s + B. Trinar-6 4.5/80 mm lens #4 (finder's lens marked as "Trinar-2" 3.5/80 #4). Without serial number on body. Very strong tripod screw on the bottom plate. Never produced unfortunately.
"START" prototype camera below from Alain&Claire Berry (France) collection.