To determine which kit # is required, verify which RPO codes are shown in the glovebox to determine the factory installed torsion keys. Any of the following RPO codes require the C1202/C1212/C31 kits: FT2 - FT3 - FT4 - FT5 - FT6 - FT7. Any of the following RPO codes require the C1203/C1213/C32 kits: FK2 - FK3 - FF6 - FF7 - FF8 - FF9.Zone Offroad torsion bar key leveling kits are made in the USA and are 100% resonant frequency tested to ensure a solid casting. Once tested the torsion bar keys are CNC machined to achieve 2" of lift with the adjustment bolts in the factory location. Zone Offroad front and rear shocks and a steering stabilizer are also available to complement to your Zone leveling kit.