The Mamiya Flex name was used for a series of fixed lens twin-lens reflex cameras built from 1948 to about 1956. These had ‘A’ and ‘B’ designations, hence the ‘C’ in the interchangeable lens models. Refer to the Mamiya web page (Section 13) for details. The dates of manufacture are very difficult to confirm. Some references quote the date of announcement, others the date of first availability in a particular country. Further more, older models would still be available new for a period. The basic C220/C330 design, with minor modifications, lasted some 26 of the 38 year production history.
TLRgraphy: Mamiya TLR has a very very unique feature…. they are very very well-built, which means they are very very heavy!!