Main equipment at underground coal mine working face. Through optimization design, the problems of roof control, coal wall stability, support stability, impact resistance and fatigue life of super high mining face are solved. ZMJ could provide 1.5-10m high shields for our client. ZMJ had provided 4m longwall system for Merge mine at south kalimantan, 4.5m longwall system for Qinfa coal mine at south kalimantan.