2005-2007 Super Duty 4x4 Full Progressive Leaf Spring Kit - 1" Lift (CS-FFSP-LVL-05)Description Designed and built by Deaver Suspension, these Carli Front Leaf Springs provide 15" of increased wheel travel, 1" of rear lift, and deliver smoother suspension cycling over terrain without the use of lift blocks with only a slight reduction from a standard 3 4 ton load capacity. These leafs feature a 9 leaf main and a 3 leaf overload for less jarring, more mobility in the lower overload, and improved spring rate progression. Part Number: