This kit fits 2001-10 2500 & 3500 HD models. For a complete list of compatible applications click the vehicle fitment tab and verify the RPO code of your truck to determine whether a C1202 or C1203 kit is required.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 a 2" of lift. Only Zone Offroad lists torsion key fitment based on the RPO codes of your truck listed in the glovebox to ensure the correct fitment. No more guessing of what color key might have been installed from the factory. Shock relocation brackets or longer shocks are required and are listed in the recommended accessories.