This is a MC Zenitar 16mm F/2.8 Fisheye Camera Lens
This lens is a manual focus lens with a Pentax M42 Screw Mount.
This lens is in good used condition. It has a nice smooth focus. Looking at the glass, there is quite a bit of dust inside, but no fungus/haze. This lens comes with both front and rear lens caps.
I am asking $125 or best offer and Shipping is $7 for anywhere in the Lower 48 US States.