Pentacon 30mm 3.5. Condition lots of brassing but elements are in decent shape, do have some dust specs. It is a very solid lens, preset. It give an extremely nostalgic look you can't find with too many lenses. Dead Link Removed
Anyone using M42 should buy this lens immediately. I own its predecessor (in Exakta mount) the Lydith 30mm F3.5 and the performance is superb. I reviewed it on my blog. Good seller too.