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. Symmetric vane, split-core castings for uniform heat distribution. Black E-Coat anti-corrosive coating protects much better than competitors spray paint. Double disc ground friction surface for optimal performance and service life This extra process provides better rotor balance and creates a cleaner; more finished looking component; In addition; Rotors are inspected for balance and mill-corrected to a tolerance of less than 2oz 2008 - 2017 Audi A5 Quattro, 2009 - 2016 Audi A4 Quattro, 2009 - 2017 Audi A5, 2009 - 2018 Audi A4, 2009 - 2018 Audi Q5, 2011 - 2018 Audi A7 Quattro, 2012 - 2013 Audi A6, 2013 - 2013 Audi A6 Quattro, 2013 - 2015 Audi A4 allroad, 2013 - 2015 Audi allroad, 2018 - 2018 Audi A7