HeatlhSmart - Memory Foam Coccyx Cushion has a contoured design and a rear cut out that reduces pressure on the tailbone. This improves posture and promotes proper spinal alignment. The memory foam cushion conforms to the body and retains its shape. It comes with breathable mesh cover can be removed and machine washed. The cover also has a non slip bottom that helps keep the cushion in place. This tailbone pillow can be used on an office chair, car seat, or wheelchair.