Purma Cameras Ltd was registered on 4 June 1935 by Alfred Mayo and Tom Purvis, better known as a commercial artist. The company received financial support from David Brock of Brock Fireworks. The Purma trade name was registered in June 1935 and the first Purma camera was based on British patents 430648 and 44907 of 1935 and 1936 respectively. Three models of the camera were produced: the Purma Speed from June 1936, the Purma Special from June 1937 to 1940 and postwar to 1951 and the Purma Plus from 1954 to circa 1956. There are a number of minor variants of the cameras and a range of accessories was also sold for them.

A fourth camera, the SAMA was the subject of patent number 684684 of 24 December 1952 but is not believed to have been manufactured although a prototype was produced.

The principal feature of the Purma cameras was the innovative gravity controlled shutter which gave different speeds depending on which way round the camera was rotated. This feature also determined the square negative format.