QA1 Coil Springs: Made from high-quality chrome silicone steel, these 12-inch, 150 lb/in springs (such as part #12-150) are heat-treated, shot-peened, and designed for reliable, high-stress suspension travel QA1 12 QA1 shocks 12-150 +5 The QA1 12-150 typically refers to a coil-over kit or spring QA1 12-150 QA1 Coil Springs | Summit Racing rated at a 150 lb./in. spring rate with a 12-inch spring length QA1 DD501K2 (DD501): Double Adjustable Coil-Over Shock Kit - JEGS. This setup is widely used for drag racing, street performance, and custom street rod applications DD501-12150 Pro Rear Weld-In Coilover Kit,
