This set is in excellent optical condition and perfect working order. Delivered as displayed with case and all accessories visible in the images. The Zeiss Stereotar C 1:3.5 f=35mm is a vintage camera lens produced by Carl Zeiss Jena, a German manufacturer of optical equipment. This lens was designed to be used with stereoscopic cameras, which are cameras that capture two images simultaneously, allowing for a 3D effect when viewed through a stereoscope. The 35mm focal length of the lens means that it has a moderate wide-angle field of view, making it useful for landscape, architectural, and street photography. The maximum aperture of f/3.5 means that it is not particularly fast, but it should be sufficient for most daylight shooting situations. The "C" in the name indicates that it has a coated lens, which reduces reflections and improves contrast. Overall, the Zeiss Stereotar C 1:3.5 f=35mm is a well-regarded vintage lens that can produce high-quality images, particularly when used in conjunction with a stereoscopic camera.