Abstract: A sprocket assembly is provided which allows a film projector or any other film handling device to be readily converted to run film having different perforation-to-frame ratios. The sprocket assembly includes an outer cylindrical sleeve having teeth for engaging the film perforations when the film is run, and an inner cylindrical sleeve adapted to fit within and anti-rotationally mate with the outer cylindrical sleeve. The inner sleeve also has teeth for engaging the film perforations. The inner sleeve is mounted on a rotatable shaft of the projector, and the outer sleeve can be added or removed.