Duro-Med Convoluted Foam Chair Pads Are Made Of Medical-Grade Foam. The Convoluted Surface Allows For Better Weight Distribution And Air Circulation. It Is Ideal For Prvention And Treatment Of Decubitus Ulcers. The Seat Pad Measures 16" X 18" X 4". Flame-Retardant, Meets Or Exceeds Cal #117 Requirements. Seat Cover Is A Plaid Poly/Cotton Cover.