“Six 20” stood for the type of film used in the camera—620 film. How did camera makers create so many different kinds of film? Kodak took control of the film industry, designating numbers for different sized film rolls. 120 film was a popular roll for “medium” format images intended for amateur photographers. It was larger than the standard 35 mm film, resulting in larger high quality images. 620 film offered similar characteristics, except it was loaded onto a thinner spool. Kodak intended this thinner spool to allow for smaller camera bodies.