These specially-designed memory foam cushions help relieve spinal pressure to ease sciatica and back pain so you can sit comfortably for long periods of time. The ergonomic design relieves pressure on the coccyx and naturally aligns the spine for healthy posture. Made with breathable memory foam, covered in soft velour, the cushions fit most chairs and are perfect to use at home, in the car or at the office. Memory foam construction with removable covers for machine washing. Lumbar Cushion: 14"L x 13"W x 5"H and Seat Cushion: 17"L x 15"W x 2"H. 2-Piece Set.