Chemical Guys SPI21516 Decon Pro Iron Remover and Wheel Cleaner, 16 fl. oz. Finish the car wash process with DeCon Pro, then follow up with clay bar service for thorough decontamination during a full detail pH-balanced formula safe for all wheel types, gloss paint, clear coat finishes, polished metal, chrome, and glass Formula neutralizes the reactions that cause rust and paint failure caused by hot brake dust particles Iron catalyst turns purple once reaction is complete Add to wheel-cleaning arsenal to remove toughest stuck on brake dust and contaminants