Lose the bumps, chucks and jars. By adding an air bag at the hitch connection, you, your towing vehicle and the coach enjoy smooth, stable towing performance. The TrailAir ® coupler's unique scissor action design acts as a buffer, cushioning the hitch area, protecting your 5th wheel trailer. The air bag absorbs the road shock. Upgrade to the TrailAir® Pin Box for an improved ride for your truck and your family, your coach and all the things that ride inside.