Product updated on 2019-05-17, Zone Offroad - ZON:C1203, 2007 to 2010 Silverado and Sierra 2500 / 3500 2 inch leveling Torsion Bar Keys, This kit will fit trucks with one of the following RPO codes : FK2-FK3-FF6-FF7-FF8-FF9. You can locate the RPO code in the glove box,