Lumex R Basic Wedge Cushion 18 x 18 x 3 1/4 4 Features a specialized gel layer with a convoluted foam topper that reduces tissue interface pressures at critical points. Incorporates a moderate wedge design sloping from 4 in the front to 3 1/4 in the rear. The soft, stretchable lightweight cover reduces shear/friction and is fluid-proof and has a strap at the back to secure the cushion firmly to the chair. Accommodates a wide range of body shapes, sizes and weights. Bariatric cushions with higher weight capacities are available. 350 lb maximum weight capacity. 2 year limited warranty. ASIN B001Q1NLIA. Category Pressure Management Wheelchair Cushions This item ships from a separate warehouse and may require extra time for delivery.