Emergency shut off valve is mainly composed of main valve 2, one-way valve 5, needle valve 1 and ball valve 3, pressure valve table 4, etc. Emergency shutoff valves are used in parallel water supply systems in fire fighting waters in residential areas. When fire water is used,the valve automatically closes domestic water and fire water. When the fire is over, the valve opens automatically to restore domestic water supply. It is more cost-effective than the traditional firefighting water supply alone. The filter should be installed before closing the valve urgently, and the requirement of convenient discharge should be required.