Wheelchair Accessories - 20" x 16" Maxx Wheelchair Cushion: 20" x 16" Contoured leg abductors and abductor promote proper position while increasing total seating surface area. The increased seating surface area maximizes weight dispersion providing exceptional pressure reduction. Four densities of HR foam are used in the construction of this cushion. It utilizes a recessed, high viscosity, three dimensional, Twin-Gel pack that protects a patient's ischial and coccyx area.