... -air tube (bent pipe), incorporated with design dust bag, keep filter from dust,keep superior suction performance;2.Design of ... -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 ...