Extremely rare prototype APO-Telyt-R 1:2.8/400mm, produced in the late 1980s and subjected to extensive field testing in connection with the 1988 Seoul Olympic Games. Following this testing phase and further optical and mechanical refinement, the final production version of the 11260 lens was officially announced only in April 1992.Compared with the later series-production lens, this prototype has noticeably larger and heavier dimensions, reflecting its original development stage prior to the significant reduction in size and weight. The lens already incorporates the impressive characteristics that would later define the production model, including apochromatic correction, internal focusing, flat field performance and neutral colour rendition. The optical construction corresponds to the early 11260 formula.Finished in the characteristic light grey, heat-reflecting paint, the prototype was conceived for demanding professional sports and wildlife applications and was never offered for public sale, remaining strictly within Leica’s internal testing programme. The offered example shows wear from years of professional use and testing, yet remains fully functional, with optics in remarkably good condition. The lens is offered complete with its original palm grip, matching lens hood, and large carrying case. An exceptionally rare and historically important Leica prototype, documenting a decisive stage in the development of Leica’s fast super-telephoto optics.