Very popular with landscape professionals and organic farmers. The 4-gallon (16-liter) HD400 has an internal mechanical agitator that does an excellent job of keeping powdered chemicals in suspension, such as kaolin clay organic insecticides. The HD400 was independently tested for more than 1,500 continuous hours of operation with no breakdowns and the Jacto HD400 is easily converted for either right-hand or left-hand operation.