Carl Zeiss Jena-made Topogon 25mm lens for Contax, manufactured around the late 1940s. It features a symmetrical design with 4 groups and 4 elements, based on the Hypergon meniscus lens design, and comes with T coating. Although it doesn't have coupled rangefinder focusing, it's enjoyable for estimating focus by stopping down. Distance markings are in meters. This ultra-wide-angle lens, created by Dr. Richter who worked at the Goerz company, was originally developed for aerial photography purposes. It's said to be extremely challenging to manufacture due to its very tight curvature and small glass elements. Only about 1000 units were produced, and this particular lens belongs to the early production batch. Please note that it may not be compatible with certain camera bodies or adapters. Feel free to inquire for further details. Rare item. The lightweight aluminum barrel shows some signs of corrosion, and there are overall scratches and signs of use, but the appearance is still clean. The operation of both the aperture and helicoid is smooth, providing a pleasant user experience. The glass has some light wiping marks and minor coating damage, but it shouldn't affect image quality. Due to its design, it cannot be mounted directly on Leica M-type cameras as it would interfere with the body's rangefinder cam. However, it can be used with adapters on mirrorless cameras. Sample images have been posted in the showroom. It has a unique atmosphere with soft peripheral rendering, and as you stop down, the rendering becomes more subdued. It's a fun lens to use. This item has been sold at the store before it was ready for sale. Thank you.