Challenger Lifts RJ9S Air Hydraulic Rolling JackChallenger Lifts RJ9S Air Hydraulic Rolling Jack Challenger Lifts RJ9S Rolling Jack features air hydraulic operation and comes standard with (4) 3" Stack Adapters. Broaden your service revenue with easy access to brakes and wheels from underneath four post lifts. 9,000 lb. capacity rolling jacks features adjustable width, low vehicle drive over clearance, stackable height extensions with built in storage rack and factory installed and protected filter