The Nikon FM is a 35mm single-lens reflex (SLR) film camera introduced by Nikon in 1977. It features a fully mechanical shutter with speeds from 1 second to 1/1000 second plus Bulb, and a flash sync speed of 1/125 second. The camera uses the Nikon F-mount, allowing compatibility with a wide range of Nikkor lenses. Metering is handled by a center-weighted, match-needle system powered by two SR44 or LR44 batteries, but the camera remains fully functional without batteries except for the meter. The FM is known for its robust, all-metal construction and manual exposure control, making it popular among enthusiasts and professionals. Notable features include a depth-of-field preview button, mirror lock-up, and a self-timer.