Gasoline 4stroke Aico Mist Sprayer/Mist Blower/

Manual Knapsack Sprayers Description: These are the most basic and oldest type. They rely on the operator manually pumping a lever (either side-mounted or central) to build and maintain pressure within a pressure chamber. Mechanism: A piston or diaphragm pump is activated by the pumping action, pushing the liquid from the tank through the hose, lance, and out the nozzle.