The Petri Penta is the first of a series of 35mm SLR cameras made in the late 1950s and early '60s by Kuribayashi/Petri (the company changed its legal name to Petri in 1962, while this series of cameras was current; they all bear the name Petri on the front of the prism). Some of the series were sold in the USA (and perhaps other markets) as the Petri Flex V, and some examples are badged Petri Flex (with no 'V'); note however that the Petri Flex 7 is not one of this series.