Badger Air-Brush Co. #121 Paint Mixer, for use with 3/4-ounce, 1-ounce, 3-ounce and 4-ounce Jars. Thoroughly mixes all types of paint. Evenly disperses pigment in its base material to assure consistent viscosity of paint from top of the bottle to the bottom. Requires 2 AA batteries (not included).