Memory Foam Wheelchair Cushion 18x16x2 w/Navy Poly Nylon Cvr 18 W x 16 D x 2 H * Navy Nylon Cover * Custom sizes available * Optional solid seat inserts are available * Foam conforms to the patientÊs body by surrounding boney prominences reducing interface pressure * Heat-activated foam self-adjusts to the seating surface to maximize comfort and pressure relief * Model 1701A foam cushion is covered using a Vyvex III low shear nylon stretch material * Model 1701 foam cushion is covered using a fluid-proof nylon material * All cover materials and foam are fire-retardant and anti-microbial * Shipping Carton Size: 23 L x 20 W x 4 H