StopTech Sport Rotors are also available with an optional cryogenic treatment. Although cryogenic treatment is invisible to the naked eye; many fleet customers are sold on its ability to extend the service life of the brake rotor. Deep cryogenic treatment is a one-time process that permanently improves the performance and wear characteristics of metal components; from brake rotors and engine parts to machine tools and gear sets. All new StopTech Sport Rotors may be ordered with cryogenic treatment for an additional fee.