Don't be limited to adjustments Completely re - valve in minutes with the MOD Series shock. Designed specifically to meet the demands required by today's high performance drag race and handlingpro - touring cars, QA1's multi - patent - pending MOD Series shock will transform the way racers respond to changing track conditions and configurations. The key element to this tunability is QuickTune Technology dry modular valve packs that can easily be swapped out, all while the shock remains on the car. An industry first, the MOD Series shock can quickly and easily be revalved without interrupting the oil path or opening the shock up for debris and air contamination. Medium compression and rebound valve packs come standard