After the war, Leitz continued to produce the late versions of the Leica II and the Leica III through the 1950s. However, in 1954, Leitz introduced the Leica M3, with the new Leica M mount, a bayonet-like lens mount. The new camera also combined the rangefinder and viewfinder into one large, bright viewfinder with a brighter double image in the center. This system also introduced a system of parallax compensation and a new rubberized, reliable, focal-plane shutter. Leica continues to refine this model (the latest versions being the MP and MA, both of which have frames for 28, 35, 50, 75, 90, and 135 mm lenses, which show automatically upon mounting).