This is anamorphic attachment for a projector lens made by Meopta.
Squeezing ratio is 1:2. Serial number is 5415.
You can use it as taking attachment as well if you
find a way to mount it onto your camera setup. This attachment has a
distance scale (from 12m to 150m).
Length is about 20cm, rear barrel diameter is 9cm.
Front glass element diameter is about 9cm. Rear element glass diameter is
68mm.
Weight is 2.1kg.
You can see sample of use of similar attachment with DSLR at following page - http://www.ixbt.com/digimage/anamorf.shtml.
It is in Russian, but you'll get an idea on how to use it with a DSLR
:-) find highly informative pictures showing resolution charts and test
shots.
The attachment is in very good used condition, though it is not perfect - some cleaning marks and dust.