Nickel Summar lens with collapsible barrel, produced by Leitz with the code SUMUS. Manufactured in 1934. Meter scale. It features a straight helicoid, hexagonal aperture, and is non-coated. With a double Gauss design comprising 6 elements in 4 groups, the aperture scale follows the continental style (f2, 2.2, 3.2 onwards). When wide open, it exhibits the characteristic flow in the periphery reminiscent of vintage large-aperture lenses, along with a distinctive bokeh typical of the double Gauss design. Despite its compact and lightweight build, it offers ample brightness with its maximum aperture of f2.0. Its retro appearance exudes the full charm of vintage lenses, perfectly complementing cameras of the same era such as the Leica DII and DIII. However, it also pairs well with modern digital cameras, allowing you to enjoy the gentle rendering of non-coated optics. A genuine front cap is included. The helicoid and collapsible parts show numerous light scratches, as expected, but there are no prominent scratches. Other than that, there is typical wear for its age, but the dull shine of the nickel plating adds a nice atmosphere. It underwent a full service in 2023. Through careful maintenance, both the aperture and helicoid operate smoothly, ensuring excellent usability. The focus is accurate, and the rangefinder coupling works perfectly. There are a few minor wiping scratches on the front element, and some yellowing due to age across the entire front element, but it's unlikely to significantly affect image quality. There is no haze on the middle element, making it quite a clean glass for a Nickel Summar. Test results were satisfactory.