This product is mainly used to coarse and mediate crush brittle materials, with wide applications in departments such as mining, metallurgy, chemical industry and coal mining, etc. With its great feeding grain size and adjustable discharging grain size, it also possesses the ability to crush materials with compression strength below 1600 Mpa. Especially when used in coal mining, this machine can directly be used to crush materials after de-ironing and trashing, with no requirements to discard gangue. Moreove, the crushed materials bear with themselves with even grain sizes and low excessive crushing ratio, so as to simplify coal dressing and decrease investment and production cost.