Aerosol paint is paint that comes in a sealed, pressurized container and is released in an aerosol spray when a valve button is depressed. Aerosol painting is one form of spray painting; it leaves a smooth, even coat, unlike many traditional rolled and brushed paints. Standard-sized cans are lightweight, portable, inexpensive, and easy to store. Aerosol primer can be applied directly to bare metal and many plastics.