Edelbrock IAS shocks switch instantly between a firm and a soft circuit for superior handling and a smooth ride. There is no other shock that can deliver this kind of performance. Why? Because no other shock has the patented Ricor Inertia Active System or IAS. Until now, if you wanted to reduce chassis roll around turns and under hard braking, yet have a comfortable ride, you couldn’t do it. No shock absorber in existence could do both without some compromise in either handling or comfort. When you improve the handling with stiffer shocks, the ride becomes rough. When you improve the ride with softer shocks, the handling becomes sloppy. Now, the revolutionary Edelbrock shocks deliver excellent handling and a comfortable ride. The patented Ricor® Inertia Active System eliminates the compromise inherent in other designs for a shock that is soft on rough roads and firm on smooth roads. This keeps the tires on the ground and the chassis stable. You may have heard these claims before, but now it’s for real. With Edelbrock, you get “The Best of Both Worlds”… superior handling and maximum comfort!