LOMO (CKBK) Experimental Projection lens OKP4-75-1
I was unable to find this lens in my reference books, unfortunately.
It is projection lens for sure. Focal length is 75 mm. High speed - f/1.6. Experimental sample made at CKBK in 1968.
They decided that there is no need to use best glass for experiments, and installed scratched second lens - see the picture. This will not affect image quality too much.
The lens is heavy - 3500 g.
Front diameter is 104 mm.
Rear diameter is 68 mm.
Length is 250 mm.