Superlift lifted coil springs for the Ford F100, F150 are made right here in the USA using Spec 5160 spring steel. They have been designed to give you the lift you want without sacrificing ride quality. Superlift lifted coil springs are fully compressed and stressed in the manufacturing process to minimize settling. For durability, the coil springs are either powder coated or vinyl coated in black depending on the application.Coil springs are sold in pairs. Superlift offers a Lifetime Warranty and Satisfaction Guarantee to give you confidence in your purchase.