BOV stands for Bag On Valve, which means valve in a pouch. BOV is one of the methods used in aerosol production, particularly in the production of food, cosmetics, and personal care sprays. In this method, the main spray substance is injected into the pouch, and the propellant gas is placed behind the pouch, in the space between the inner wall of the spray can and the outer layer of the pouch, without any contact between the liquid and the propellant gas.