and case are both made of high quality stainless steel with the advantages of stain resistance and durability.Equipped with ozone generator, the machine has more advantages:Adopt ozone generator to sterilize quickly. If the concentration of ozone in water is 0.4mg/L, the colon bacillus, ect.will die in 0.25-1minute,and the hepatitis virus will die in 1minute in 4-mg/L ozone water.