Fox Valley Traders Contoured Cushion with Coccyx Cut Out Relieves Back Pressure  You can use this memory foam seat cushion to relieve pressure on the lower spine Portable Seat Cushion  With a small size and lightweight foam interior, youll be able to take this cushion wherever you need a bit of extra support when sitting Contoured Cushion for Comfort  The U-shaped cutout at the back and contours in the memory foam coccyx cushion will deliver a high level of comfort for any type of chair Washable Mesh Cover  Should the cover become soiled, just remove it and toss it in a washing machine without affecting the foam interior Posture-Enhancing Cushion  The contours in this back-support cushion encourage you to sit with a proper posture in any chair