The Contax S can be said to be the camera that defined the configuration of the modern 35mm SLR camera. Not only did it introduce the M42 lens mount which became an industry standard, but it was also equipped with a horizontal focal-plane shutter, and also removed a major objection against the reflex camera by offering an unreversed, eye-level viewing image by employing a pentaprism. Introduced in 1949, the S was followed by numerous models including D, E, F, FB, FM and FBM. During that period, VEB Zeiss Ikon, as the firm became known, was gradually under pressure from the new Zeiss Ikon AG in the US zone, so the original Zeiss Ikon and Contax names and trademarks gradually disappeared and were replaced by the new name of Pentacon, which never really caught on. Finally, this camera line was abandoned.