BPremier Comfort Visco Memory Foam Wheelchair Backrest Size: 18" H x 18" W ReviewbP PP Premier Comfort Visco Memory Foam Wheelchair Backrest Size: 18" H x 18" W PAvailable in three different sizesPLumbar and side lateral supportPMemory foam forms to unique body shapePGreat for wheelchairs scooter seats and office desk chairsP