this lens is completely unmarked, as is the housing altogether. it has a built in sun-hood and coated lenses, no sratches, no mould.
aperture mechanism can be switched from automatic to manual and respnse is prompt, all is working fine and smooth.
. aperture ranges from 4.5 to 22. distance is shown
in meter and feet. . a semi-soft carrying bag is also included. filter thread is 67mm, lens no 17103927, no filters included.
lens length is 21cm, lens lids are included. the lens looks, as if it had hardly been used, but none of the mechanisms/rings are sticky.
it has a tripod connector mounted to it, which can be rotated on a ring at photographers convenience.
M42 thread is perfect and unmarked, I tested it, as I have a Exa II M42 camera.