whirl charging aerator CE,UL,CCC approved, IP55(nsulation class F) Precise impeller and cover 100% Oil Free Air FeaturesCentrifugal vanes make high pressure, great outflow and low noise.High quality engine ensures safe and steady effect.Non-oil lubrication and pure compressed air.Phosphorize disposition, regular coloring and adhesive strength.Wide range of power, long life os this machine. ...