QA1's GM Coil-Over Shock for 1963-1982 Corvettes, 1965-1996 Impalas and 1958-1996 Full Size GM vehicles, including Full Size Chevy, Buick, Oldsmobile and Pontiac models, is a great choice for anyone looking for adjustable valving control. Choose the valving to match your driving style and you're on your way. This shock is a great option for anyone looking for a suspension upgrade for their street car. Adjustable Coil-Over Shock Features:, Available in independent compression and rebound double adjustable, simultaneous compression and rebound adjustable, or drag "R" Series adjustable, Lightweight Billet Aluminum Coil-Over Shocks, Made in the USA, Easy, Bolt-In Installation, Ride Height Adjustable, 100% Dyno Tested and Serialized, Serviceable and Rebuildable by QA1 Authorized Service Centers, Made in the USA.