A) Product description ?? The device used for fighting fires and class B A, Class B fire mix; can be used independently as the fire protection equipment, and can be used with large fixed foam fire fighting systems play a supporting role, mainly for oil, oil District and refineries, petroleum, chemical industry, oil ports, hangars, garages, warehouses, gas stations and other places. Has good mobility, flexibility, can grab and foam, foam generators and other components of low, medium and high expansion foam fire extinguishing systems. (B) the working principle of the apparatus body by Q235 steel plate, using PHF-type negative pressure proportioner, which is the principle of making use of the venturi at the exit of processing a negative pressure through the pipette solution intake ratio of the foam from the tank mixer, the mixture is mixed with water and bubbles, fire fighting foam formation of air through the air bubble gun.