Powder coating is a process by which a coating of pigment is applied to the surface of an item to create a layer of color that is brighter, thicker and much tougher than conventional paint. It involves the use of a dry powder which is sprayed onto the cleaned surface of the item in question. The powder is held on by means of an electrostatic charge imparted to it by the specialized spray gun that is used. This powder is made of a special thermoset polymer, which responds to heat. When the powder is baked, it reacts with other chemical groups in the powder polymer and increases the molecular weight and improves the performance properties of the material, creating a smooth and uniform layer of pigment. This process is used primarily on metals because of the high temperatures that the powder must be cured at. One will most commonly see power coating on processed aluminum goods and appliances as well as automobile and motorcycle parts.