Poorboy's Iron Fallout Remover breaks up, dissolves and removes ferrous metallic iron particle contamination caused by rail dust, brake dust and industrial fallout. Iron remover from Poorboy's world may be used on all exterior painted surfaces, wheels, glass and chrome. Although poorboy's iron remover contains no dyes, a chemical reaction that produces a colour change occurs as it is breaking up and dissolving ferrous metals. This product will turn red/purple when sprayed on to a surface that is contaminated with iron particles. This is most easily seen on lighter colour vehicles but decontamination performance is equal on all colours. This lets you know iron is present and that Poorboy's Iron Remover is working too remove iron particle contamination.