Tamron ended production of GS-1 cameras and lenses in June 2002, with sales continuing until stocks were depleted. It is a completely modular camera, with several optional focusing prisms and viewfinders (with and without exposure metering), lenses, and film backs. Introduced in March 1983, the Bronica GS-1 in 6×7 cm format was the largest SLR produced by the company and the first medium format camera with TTL flash metering.