Tein SKP26-BUB00 High.Tech Lowering Spring for Nissan 350Z Front spring rate: 6.4 kilogram per millimeter (358 pounds per inch) Rear spring rate: 6.7 kilogram per millimeter (285 pounds per inch) Front ride height: -13 millimeter (-0.5 inch) Rear ride height: -7 millimeter (-0.3 inch) Progressive spring rate design