A machine that combines coal crushing and screening. It consists of a revolving cylindrical screen 8 to 14 ft (2.4 to 4.3 m) in diameter and 13 to 22 ft (4.0 to 6.7 m) in length. It breaks the coal by gravity impact. On reaching the desired size, the coal is 393 discharged through the plates. It can deal with run-of-mine coal up to 12 in (30.5 cm) at a rate of 500 to 600 st/h (454 to 544 t/h), to give a product size of below 1-1/2 in (3.8 cm); other sizes can be produced, depending on the screen plates used.