2.5/28mm lens RO61-1, PSK mount
The lens was made at Lenkinap (renamed to LOMO later) in 1959 (#591501).
Glass is coated. Follow focus gear has industry standard 32 pitch.
Excellent mechanical and optical condition. No fugus, no scratches.
The lens has PSK mount (precision 35mm film movie camera with focal-plane shutter, not reflex).
You may try to adapt it to your camera.