16 mm film is a historically popular and economical gauge of film. 16 mm refers to the width of the film; other common film gauges include 8 and 35 mm. It is generally used for non-theatrical film-making, or for low-budget motion pictures. It also existed as a popular amateur or home movie-making format for several decades, alongside 8 mm film and later Super 8 film. Eastman Kodak released the first 16 mm "outfit" in 1923, consisting of a camera, projector, tripod, screen and splicer, for $335. RCA-Victor introduced a 16 mm sound movie projector in 1932, and developed an optical sound-on-film 16 mm camera, released in 1935.