Wheelchair Accessories - 20" x 16" Medline Wedge Wheelchair Cushion: 20" x 16" Medline Wedge Cushion Has a Combination Foam and Gel Design for Pressure Sensitive Patients This therapeutic cushion has a wedge design that helps prevent patients from sliding forward. Two layers of high-density foam provide a stable foundation, while the four-section gel pack helps relieve pressure. ShearX all-way stretch cover reduces skin shear and is antimicrobial and fluid-proof. Cushion has a non-skid bottom and a strap to hold it in place.