The Zeca-Flex was a 6×6 folding TLR, made in Germany by Zeh in 1937. There were various selections of taking lenses, such as a Schneider Xenar 75mm/3.5 in Compur or Compur Rapid shutters, with a Sucher-Anastigmat f2.9 viewing lens.
Folding TLRs were more complex, and not much smaller than non-folding TLRs - and were not popular.
Links & Sources
- McKeown 12th ed. p1035.