This is an M42 mount lens. It's an old lens, but while there are some scratches on the exterior, it's a clean used item with no operational issues. A lens with a focal length of 135mm and an aperture of f/3.5, made by Pentax. - Model Name: Super-Takumar 135mm f/3.5 - Country of Manufacture: Japan - Aperture: f/3.5 - f/22 - Focal Length: 135mm - Design Features: Ribbed body Thank you for viewing.