Every spring is computer tested as the last step?every spring, not just a sample from each batch. Each spring is loaded in the spring tester at the factory, then compressed and the CNC load cell measures the force for a variety of spring lengths. This allows BMR to offer a LIFETIME WARRANTY against spring sag.Blending aesthetics and performance, BMR has designed the SP112 for the street performance crowd who want to use their cars in a variety of application. These springs will drop the back of your V8-equipped 2008 and newer Challenger 1.25-inches, and feature a 720 pound/inch spring rate to give you great handling and a smooth ride. The linear spring rate offers plenty of support, keeping the body flat and level in the corners, while remaining soft enough for a comfortable ride on any road. When performance and looks are a must, rely on BMR's suspension!BMR's suspensions SP112 lowering springs are available in red powdercoat for long-lasting good looks. Installation time is about 2-3 hours. Proudly made in the U.S.A.