The McCloskey SF50 portable feeder stacker features variable speed to prevent material from building up in the hopper, which contributes to controlled flow, according to the company. It is powered by a 74-horsepower Caterpillar engine, and can produce up to 500 tons per hour. It has a 50-foot main conveyor with a 40-inch-wide belt. Discharge height can be adjusted to up to 6.5 meters.