BackJoy is an innovative, proven back pain cushion that provides natural, safe and effective back pain relief by optimizing your posture. Perfect as a coccyx seat cushion, office chair cushion, and for tailbone relief. This orthopedic seat cushion helps to improve your lower back posture and relieves lower back, tailbone and lumbar pain, as well as other types of coccyx or back issues. Portable Cushion: Easy for travel. Works for car seats, office chairs, hard surface chairs, desk chairs, outdoor surfaces, and driving.