This is a Canon 7 rangefinder camera with a selenium light meter.Lens Mount: Uses the Leica Thread Mount (LTM) M39 system, allowing for a wide range of interchangeable lenses.Viewfinder: Features a combined rangefinder/viewfinder with adjustable bright lines for 35mm, 50mm, 85mm, 100mm, and 135mm focal lengths.Light Meter: Includes a built-in selenium cell light meter on the top deck, which does not require a battery to operate.Production: Introduced in 1961 as Canon's top-tier 35mm rangefinder during their golden age of rangefinder production