Rolleiflex (twin-lens reflex)

The Rolleiflex is a line of medium format twin-lens reflex cameras made by Franke & Heidecke of Braunschweig, Germany, first released in 1929. One lens forms the image on a ground-glass viewing screen while the matched lens below exposes the film, producing square 6x6 cm negatives on roll film. Later models such as the 2.8F kept the same layout.

Text from OyList