Red marker in viewer shows that the advancer knob needs to be winded. Of this the name - Signal Nettar.
Shutterspeed:
B, 25, 75 & 200.
Vario shutter.
Nettar-Anastigmat lens.
f: 4,5 / 75 mm.
Manufactured by:
Zeiss Ikon.
Stuttgart,
Germany
Year
of manufacture:
1949 - 57.
Size:
6 x 6 cm.
Film type:
120 film.
