whip on driveways, bumps & dips. This new Motion Control Unit is designed specifically to help vehicles with existing air suspensions. It responds instantly to compression force introduced by roll, sway, or bounce on the spring of your air suspension. Each unit operates independently both front & back and on each side of the coach. These units act like valving found in many shock absorbers. They produce a smoother, stable ride. You feel the difference immediately in easier, more comfortable driving. In fact, after installation, you can simply drive the rig across the parking lot to feel the difference. Mfr. lifetime warranty. The Motion Control Unit features these benefits: Stabilizes ride for comfort & safety. Eases driver tension. Simple design to last the life of thecoach. | Hendersons Line-up SuperSteer Motion Control Unit, One-Quarter - Under 30,000 GVW