Can you Help Identify This Old Lens?

[n2mf]

The lens pictured was in a lot of photography equipment that I recently acquired. I'm trying to identify it. Age? Brand? Camera mount? Type of camera, etc? There are no names at all anywhere on the lens. As you can see it's missing the front element, however it still forms an image and has a working aperture. Any help would be appreciated.

 

[Fixcinater]

Soviet short tele for the Contax/Nikon mount.

Jupiter-11 from the max aperture, but I can't find any photos of panda versions.

 

[Patrick Robert James]

That looks to me like an early Zeiss 85mm Triotar for their Contax I cameras. Other companies made lenses for Contax as well way back then, so it could be something else. It is most certainly a lens in the 85mm range.

 

[AgX]

Soviet short tele for the Contax/Nikon mount.

The Contax mount has no snap-lock at the lens side.

 

[AgX]

The Contax mount has no snap-lock at the lens side.

Sorry, I was telling nonsense!