CONTAX 3/4/5 Carl Zeiss Jena 5cm f= 1:2 collapsible lens. For Contax RF & its mount clones: KIEV-3 & 4 modes and Nikon RF. Lens works as it should, this is a nice little piece that I used with my Kiev-3 range finder. In a collapsed mode it allows camera to be carried nicely in a pocket. This is a over 70 years old beauty of German Manufacturing. The lens is sharp even wide open, but it also depends on a film. The lens was kept at all times of no use inside of a custom velvet lined box I had build for it. I see no fungus or haze, but check the pictures first! I am offering a local pick up.
Lens can be used on modern mirrorless cameras with adapter, on Kiev 3/4/5 or any other CONTAX clone camera.