This stylish folding 35mm rangefinder camera was manufactured from 1954 to 1958. It was available with either a Rodenstock or a Schneider interchangeable 50mm f/2.8 lens. Eastman Kodak apparently only imported Schneider-equipped cameras into the USA, so in the States Retina IIc cameras with the Rodenstock Heligon lens are few and far between.
The IIc ("Small c") and (IIIc) introduced the interchangeable front elements that allowed the photographer to use either a 35mm wide-angle or 85mm telephoto component. Only the II and III series allowed accessory lenses, presumably because they have coupled rangefinders. However, the rangefinder is not coupled to the accessory lenses, and the user has to reset the lens using a scale on the underside of the lens. It isn't very convenient. The IIc and IIC lacked a meter. These IIc and IIC cameras use a Schneider-Kreuznach Xenon 50mm f/2.8 lens and Synchro Compur shutter.
The IIC ("Big C") differed from the IIc in that it has framelines in the viewfinder for the 35mm and 80mm accessory lens elements. The top deck also is a bit taller (1mm) than the IIc, possibly to accommodate the larger viewfinder/rangefinder windows. The rangefinder in the "Big C" cameras uses a central circular spot, while the "Small c" cameras uses a diamond. I think the diamond is a bit easier in use. But the viewfinder image definitely is larger and brighter in the "Big C" cameras.
The II and III series cameras also came with Rodenstock lenses standard and accessory. One point to note. If your camera was fitted with a Schneider-Kreuznach or Rodenstock lens, then you had to use the corresponding accessory lens. For example, you couldn't use a Rodenstock telephoto lens with a camera whose normal lens was a Schneider.
This camera has signs of use and age. Everything appears to work as it should. Selling AS-IS