The rectangular pc measures 17” long by 8” wide Excellent condition Gift that wasn’t used BetterBack allows you to effortlessly sit in perfect posture, easing back pain—and helping prevent it. Lightweight and portable, it makes every chair ergonomic. Wearing it for just 15 minutes a day can retrain your body’s default posture, so when you stand or sit without BetterBack, your posture is greatly improved.