in 1939, kamerawerk niedersedlitz dresden presented the praktiflex at the leipzig spring fair. the camera was a waist type with an m40x1 screw mount and a horizontal cloth focal shutter. this camera is the pattern for most of the 35 mm slr cameras, and also the japanese and the digital slr cameras today. after the war, praktiflex was the most manufactured 35 mm slr in dresden, especially for the russians as reparations. kw changed to the m42 screw mount invented at zeiss for contax s--later used by pentax, yashica and others to become a near universal mount. in 1949, it was redesigned with longer shutter speeds. the name was changed to praktica. in 1958, kw niedersedlitz became a part of the veb kamera- und kinowerk (old zeiss), later veb pentacon. praktica was typically a consumer/ amateur camera. many developments were added. it was produced until 2000.