Lenkinap 2/75mm lens RO60-4 #580716, OCT-18 Konvas mount
The lens was made at Lenkinap (renamed to LOMO later) in 1958. I heard opinion that RO series lenses are even vetter than later OKS series since they were made of trophy German and UK glass, but can't confirm or disprove these rumors.
16 diaphragm blades provide perfect bokeh. Cine optics gives soft image. 75mm focal length is one of the best choices for portrait photography. The lens covers full 35mm frame (24x36mm) easily (though it was purposed for 35mm cine cameras). Depth of field is shallow enough to separate an object from background clearly, that gives excellent impression and add cine-like feeling to a video shot with such lens. Combine all this factors, and you'll understand why so many people hunting for such lenses to adapt them for their DSLR's and camcorders.
Aperture scale is marked in f-values (2-22) and T-values (2.5-22).
The lens has so called OCT-18 mount for turret version of Konvas (Russian 35mm film movie camera).
Excellent used condition. Mechanics is smooth. Glass is clean and clear. Can't see even cleaning marks - just some dust particles.