This is a very nice example of a Rodenstock Apo-Sironar-N large format camera objective, 150mm focal length, and f ratio of 1:5.6. It is mounted in a gutted shutter, so there is no aperture iris and no timing mechanism (lens is always wide-open). The lens assembly is in very fine condition, although there are some bits of dust on the elements. No coating blemishes, no delamination, and no scratches or pits in the elements All you need is to mount the lens in a suitable size 0 shutter (such as a Copal 0 or a Syncrho-Compur 0) and you will have a great 4x5 format normal objective. The lens image circle is 76 degrees with an image circle of 214mm, so it will accommodate extensive tilts and shifts. Serial number of the lens is 11551585..