The Monroe Reflex truck shock absorber with the patented ASD Technology combines specially tuned valving with a Fluon banded piston. The ASD valve has the ability to sense acceleration to improve the handling, safety, and overall ride characteristics of sport-utility vehicles, mini-vans and light trucks. The ASD base valve will sense a bump in the road and automatically adjust the shock to absorb the impact, leaving the shock with greater control when it is needed. The features of the Monroe Reflex truck shock absorber make it the superior shock for improved handling, safety, and comfort in all road conditions.