The Nikon 55mm f1.2 AI Nikkor is a totally normal-sized lens with a super fast f1.2 aperture, which is impressive! Standard 52mm front filter thread, too. Image quality at f1.2 is soft- don't expect complete sharpness, because it's not happening- but it sure looks nice. Sharpens up well a few stops in. Cosmetic condition is excellent, with minor wear from normal use and handling; focusing action is good but slightly uneven. Diaphragm is clean and snappy. Minor dust in the optics, but there's a lot of optics so that's not a big surprise. Big fan of this lens.