2020 GM 2500 HD;Models with 3-5"" lift;Sold as a pair;2.5"" body outer diameter paired with a full bore piston to maximize damping capability;6061-T6 impact forged aluminum body for increased strength and lower shock temperatures;Hard anodized body finish for increased strength and lower shock temperatures;Tuned specific to the vehicle application to maximize ride quality and suspension travel;17-4 stainless steel chrome plated shaft for strength and corrosion resistance;3/4"" OD shaft for reduced seal friction and gas force;Internal floating piston separates nitrogen and oil to improve damping response and eliminate cavitation;California Residents:WARNING