The Marioflex is a twin-lens reflex camera for 6x6 cm pictures on 120 film, made by the obscure Japanese maker OMS Optical in about 1953. The camera has a coated 80 mm f/3.5 Rozeck lens. The examples cited in Sugiyama have a Mario B shutter, with speeds 1 - 1/200 second, plus 'B'; Barry toogood's TLR-Cameras.com shows what he believes to be a late example, with the lens labelled as an Osiro Kogaku Rozeck (OMS apparently became Osiro Kogaku, making its only other known camera, the very similar Osiroflex in 1955). This example also has an NKS shutter, with the same range of speeds.
- McKeown, James M. and Joan C. McKeown's Price Guide to Antique and Classic Cameras, 12th Edition, 2005-2006. USA, Centennial Photo Service, 2004. ISBN 0-931838-40-1 (hardcover). ISBN 0-931838-41-X (softcover). p757.
- Sugiyama, Kōichi (杉山浩一); Naoi, Hiroaki (直井浩明); Bullock, John R. The Collector's Guide to Japanese Cameras. 国産カメラ図鑑 (Kokusan kamera zukan). Tokyo: Asahi Sonorama, 1985. ISBN 4-257-03187-5. Item 2174; cited by Barry Toogood, referred below.
- OMS and Osiro cameras, including pictures of a Marioflex, at Barry Toogood's TLR-Cameras.com.