The Hardflex is a Japanese large format SLR sold around 1926, certainly having a focal plane shutter. It is only briefly mentioned in Lewis, and no other source has been found so far.
- Lewis, p.36.
- Lewis, Gordon, ed. The History of the Japanese Camera. Rochester, N.Y.: George Eastman House, International Museum of Photography & Film, 1991. ISBN 0-935398-17-1 (paper), 0-935398-16-3 (hard). P.36.