Not an F-mount. ・Mount: Contax/Yashica A 100mm lens capable of high-quality macro photography. There is some small dust inside the lens, but I was able to take beautiful pictures without any problems. C/Y CONTAX YASHICA - Brand: Carl Zeiss - Model Name: Makro Planar 2.8/100 - Country of Manufacture: Japan - Aperture: f/2.8 - f/22 - Lens Diameter: Approximately 62mm - Focal Length: 100mm Please refrain from purchasing if you are concerned about fine dust particles inside the lens. There are slight scratches from use, but it is generally clean. As I am not very knowledgeable about cameras, I would appreciate it if you could make your judgment based on the photos. If you would like additional photos, please feel free to comment. [Other] Although we have inspected and photographed the item, there may be oversights. Please check the photos and purchase only if you are satisfied. The item includes what is shown in the images. Returns are not accepted to prevent product substitution. This is a used item, so please refrain from purchasing if you are looking for perfection or are overly sensitive. Thank you for viewing. J