QA1's unique torque arm design maximizes performance without the inherent binding issues of other systems, all while achieving a 4" to 7" drop. This bolt-in system also offers incomparable adjustability: the watts link, torque arm, trailing arms, bracket mounts, and shocks are all adjustable. Double-adjustable shocks offer independent rebound and compression tunability. Great for trucks that will see track time or drivers who really want to dial in ride quality and performance handling on the street. With registration, your shocks can be backed with a best-in-class Limited Lifetime Warranty. Keep your rear end housing center in the truck with QA1's unique watts link design. This compact system keeps your tires from rubbing the sides of your bed, while providing clearance for rear exiting exhaust systems. Adjustable lower trailing arms allow you to dial in your wheel base for the perfect wheel and tire fitment inside your wheel well. Parts come powder coated and ready to install with all necessary hardware. You can bolt up the kit right in your garage or work with your local shop. Made in the USA. Fitment Notes: This system only fits short wheel base trucks. Designed to use stock '73-'79 F100/F150 9" axle with iron 3rd member and direct fit aftermarket 9" axles with iron 3rd member. Aluminum 3rd member will NOT work.