MAMIYA SEKOR SEIKOSHA-S 28mm f2.8 Lens isn't fully functional. In excellent cosmetic condition - no dents damages or missing parts. Fires at various speeds - someti.es blades not opening - usually on higher f stops and faster shutter. Blades clean and undamaged. Unmarked glass - few dust spots in taking lens. Aperture and speed adjust without any issues. No fungus.