You will not regret your decision to invest in one of these unrivaled pillows. Its stretch nylon cover is comfortable, breathable and fluid resistant. Designed with high density and resilient foam, the coccyx cushion contains state-of-the-art gel technology that provides extreme comfort and transforms your chair into a premium seat. Gel Infused Foam Wheelchair Seat Cushion w/ Coccyx Cutout -28" x 20" x4” If you work long hours sitting in front of a computer, spend many hours on the road, or are confined to a wheelchair, ProHeal’s gel coccyx seat cushion is a dream come true.