This Franke & Heidecke Heidosmat 150mm f2.8 is a projector lens from a Rollei P11 medium format projector. You can use it as a replacement lens on a P11, of course, but it's also a popular choice to convert into a camera lens. Very light patterning, some light dust, otherwise quite clean. Includes front cap.

Please note: you can not directly mount this lens to any camera. If you would like to mount this to a camera, you will have to make it work on your own somehow. We can not guarantee that it will be suitable for any application other than that for which it was originally intended: a lens for the Rollei P11 projector.