Add a little extra cushioning to a car seat without adding volume. The 1" thick foam on the 17" x 17" seat adds extra cushioning without extra height for more comfortable sitting experience. The 18" H x 16"W back features a removable lumbar cushion that cradles the back to help provide posture support. Dog bone shaped lumbar cushion is 10" x 6" with soft, supportive poly fill. Attaches to seat using included elastic strap. Easily folds when not in use. Spot clean.