Gel Wheelchair Seat Cushion, Relieve Sciatica, Back, Coccyx, Pressure Sore and Ulcer Pain, Refreshing Ergonomic Chair Cushion with Waterproof Silk Fabric, Anti-Slip Cover, Removable Strap. Built for Daily Seat: This pressure relief cushion 18"L x 16"W x 3"H fits most wheelchairs for adults, and it can turn seats of office chairs, desk chair, car seats, and dining chairs into comfortable seats.
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