... Safety Valve , Water-proof capability ,keep water from motor ;3.The product is made of advanced engineered plastic (PP) , ... -proof , alkali-proof ,anti-corrosion and more;4.Adopt professional Vacuum Cleaner’s motor , water absorption , oil-Absorbing ,acid suction, Dust ... the motor temperature is kept constant state;6.Four-layer filter system , Air Emissions 100% cleanly ; secondary pollution will not ...