This is a listing for an Industar-50, known as a pancake lens. It is a rare, early silver model. It is an M39 mount, but can be used with M42 adapters by attaching an M42 conversion ring. The conversion ring is included. Please note that this is not a Leica L mount (l39). When connected to an M42 mount via the conversion ring, the position of the lens markings may be slightly misaligned. This does not affect the image quality at all, but I have mentioned it for those who are very particular. This lens is also popular as an entry-level lens for old lenses. There are some scratches on the body, but it is in good condition for an old Russian lens. This lens has been disassembled and cleaned, and dust has been removed as much as possible. Due to the structure, dust is likely to enter, and there may be some minor dust particles, but they are minor and will not affect the image quality. The focus ring has also been greased, so it moves smoothly. There may be some wiping marks on the lens surface, which are characteristic of Industar lenses, but they do not affect the image quality. Both the focus ring and the aperture ring move normally. Overall, this lens is in good condition. If you win multiple lenses, I will combine shipping whenever possible. As an aside, if you do not have an adapter, I recommend purchasing a K&F Concept adapter. Inexpensive adapters that can be purchased for under 1000 yen may lack precision, and it is safer to purchase a well-made one. If you have any questions, please ask. I will answer them as best I can. I am also listing other rare old Soviet lenses, and I plan to increase the number of listings, so please take a look. Disassembled and cleaned Industar-50 50mm f3.5 M39 M42 Silver Old Lens Zeiss Tessar 1