Protekt O2 Wheelchair Cushion 18 x16 x4 with Pump Parallel Bars 4 above，iOS 9 8975 4 above，iOS 9 density foam * Middle layer: 2 An excellent choice for the prevention and treatment of pressure sores * The soft interconnected air cells allow for deep immersion providing constant low pressure across the entire seating surface * Adjustable air cells offer deep immersion to provide excellent pressure redistributino for tissue protection and treatment * Dual valve compartments address seating challenges such as pelvic obliquities sacral seating and enhances posture control * Both compartments can be adjusted indepedently to increase positioning and stability for side to side control * Nilon breathable cover with non skid bottom and safety straps * Easy to use hand held inflation pump * Flame resistant latex free neoprene * Patch kit included * Weight capacity: 500 lbs * Warranty: 5 year prorated *