The basics The Preval Spray Gun is a versatile spray applicator for all kinds of liquids.  The benefits Each spray gun comes with a refillable container jar that can hold whatever fluid you choose, and a power unit that sprays up to 16 oz. of liquid, depending on viscosity.  The uses The power units are disposable, when depleted replace with a new power unit.  The bottom line Jars can be swapped out any time the project requires.