This is a 29mm f:2.8 Carl Zeiss Jena lens with an M42 mount and a Canon EOS adapter (with AF confirm). The lens is in virtually MINT condition, (I cannot find a single blemish). Comes with front and rear lens caps although not with a rear cap for the canon adapter.
This is a clasic manual focus lens with beautiful colour rendition and 'bite the back of your hand' sharpness.
To see images produced by this lens see here: https://www.flickr.com/photos/22558540@N06/sets/72157620778048618/
Absolute bargain and soon they'll all be gone.