Nikon 50mm f/1.8 AF-D, the fastest lens ever made by Nikkor. It's even faster than the newest Nikon 50mm f/1.8G or 1.4G AF-S. The only downgrade is it doesn't have the rubber sealing at the metal mount to protect the censor against dust/moisture. Not really a problem, we've been using these lenses for years. Just be careful when changing lenses or shooting outdoor under bad weather conditions.