ECS GEOMET® premium brake rotors start with quality materials and precision machining. That would be enough for most of us, but it is only the beginning. To prevent brake pad deposits for better braking, select a slotted ECS GEOMET rotor. Slotting cleans the pads by moving water, gases, and contaminants away from the pad/rotor contact surface. To prevent rust pitting and corrosion damage, ECS GEOMET rotors are bathed in a special water-based solution, then heated to cure the coating and remove all oil residue remaining from the manufacturing process. These added steps create a durable, lasting rotor surface that resists road salt, solvents, and other corrosives. GEOMET is a proprietary water-based coating that contains metal oxides, metallic zinc, and aluminum flakes. More environmentally friendly than other treatments containing toxic metals,GEOMET coating contains no nickel, cadmium, barium, or mercury. GEOMET: a name and a process that make a premium brake rotor with extended service life and improved braking characteristics. From VIN #Y-005-001 which is model year 2000 up & through 2003 there are two different rear braking systems for Audi A8's. One has 269x22 rear rotor & the other has 280x22 rear rotor. Take note of your particular size & order the correct rotors.