Our rangefinders use what is called a leaf shutter; a shutter consisting of very fine identical overlapping metal blades (leaves) which open and close in order to expose the film for a specified period of time to capture an image. The shutter is a clockwork mechanism and is powered by a strong spring tensioned by setting the shutter speed before each exposure.

The manufacture of these shutters is highly specialised and camera manufacturers do not make their own. Shutters most commonly found in these rangefinders were made by Japanese companies Citizen, Copal and Seiko.