H&R'street Performance Coil Overs are the perfect suspension'solution for discerning drivers-from daily drivers'to serious tuners-who can appreciate awesome handling and superb ride comfort. Each coil over shock is custom valved to work in conjunction with a precision-engineered progressive rate spring, creating a finely tuned suspension'system. The fully threaded shock body allows for adjustable vehicle height. This feature helps balance vehicle weight, resulting in a lower center of gravity and improved performance and control. Installation Instructions