f/4.5-f/16, 5 aperture blades, click stops only at full f-stops
cooke triplet (3 elements, 3 groups)
39mm screw mount, no filter threads, light metal construction
No focus helical, must be used on bellows or extension tube.
Working distance on bellows from 12' to 7" . Infinity focus possible, but not practical
Magnification to about 1:1