Black 18 W X 16 D X 3 Custom Sizes Available Optional Solid Seat Inserts Available ($8.75 Up-charge) Relieves Pressure At The Sacral Area While Offering Patients Comfort And Even Distribution Of Weight Throughout The Cushion Medium Density Fire-retardant Foam Is Covered In Either A Poly/cotton In Your Choice Of Black Navy Or Gray Medical Grade Vinyl Shipping Carton Size: 18 L X 16 W X 5 H