The lens has been fully serviced, CLA'd (cleaned, lubricated, and adjusted)! High quality, heavy, brass mechanics, with easy and smooth operation, and cca eternal lifespan! Glass: Fully cleaned, clean glasses, and excellent coatings! Steinheil lenses are very rare with such good coatings! Focus: The focus is precise, smooth and easy to handle (even with one finger)! A fully cleaned, high quality, heavy, brass mechanics! Aperture: The aperture works perfectly in both Auto and Manual mode! The blades are clean and snappy! PS: That you can see a small part of the aperture blades from the front even wide open is completely normal at this lens, since, unlike in other Double-Gauss lenses, here the front lens section is much bigger than the rear elements!