RK Series Premium Plain Solid 1-Piece Rear Brake Rotors (RK7145) by EBC®. Quantity: 2 Per Pack. This replacement Rotor Kit is sized and shaped to OE factory dimensions with the strictest quality controls and machined to be within extremely tight tolerances of less than 0.05 millimeters. High quality “gray” iron meets or exceeds factory original specifications regarding thermal buildup, brake noise, vibration, and wear. The anodized layer is designed to disappear in the area that the brake pads contact the rotor.