Tein SKM66-BUB00 High.Tech Lowering Spring for Mazda3 Front spring rate: 2.6 kilogram per millimeter (146 pounds per inch) Rear spring rate: 4 kilogram per millimeter (185 pounds per inch) Front ride height: -25 millimeter (-1 inch) Rear ride height: -14 millimeter (-0.6 inch) Progressive spring rate design