Tokyo Kogaku, 7.5cm F3.5, a take lens for a twin-lens reflex camera with an M39 mount is up for sale. Before the widespread availability of small cameras using 35mm film, twin-lens reflex cameras using 120 film (also known as "Breezy" film) were a huge boom, mainly from the late 1940s to the 1950s. They were easy to manufacture due to their simple structure and mechanism, and the fact that parts like shutters were sold as assemblies, leading to mass production. So many twin-lens reflex cameras were released that it was said that the brand names covered all the letters of the alphabet, from A to Z. Among them, Tokyo Kogaku (Topcon), which released the "PrimoFlex," was a company that produced lenses of a high level, comparable to Nikon at the time. Even now, the "PrimoFlex" is a popular model among twin-lens reflex cameras. I think the secret to its popularity is that the images are stable and well-captured. This is a take lens from the "PrimoFlex," converted to an M39 mount lens. It is an M39 mount, not an L39 Leica mount. Since the thread pitch is the same, it can be attached to a Leica, but focus will not be achieved unless the flange back is adjusted. There are few scratches, and some cloudiness is visible in the lens. In actual shooting, the effect of the cloudiness was not very noticeable, but please refrain from purchasing if you are concerned. The shutter has been removed when the lens was disassembled and cleaned. It is a triplet lens with 3 elements in 3 groups. Since it shoots in the center of the 6x6 format lens, the drawbacks of the triplet lens are resolved, so I think there will be little aberration in the shooting surface. For those who love twin-lens reflex cameras, those who love Tokyo Kogaku, and those who love classic lenses, please consider this item.