A 16" x 12" multi-functional air pillow, the Back Vitalizer™ offers multiple ways to relieve back pain: When laid upon, it bridges the lumbar spine for decompression of the discs. Placed on a chair behind the back, it functions as a lumbar suport. When sat upon, it functions similar to an exercise ball activating the deep stabilizing muscles of the spine for core stability. On the seating surface, it functions as a posture positioning wedge. In standing, it can be used for ankle rehab and balance training. Premium biodegradable polyurethane coated nylon is durable and easily washable. Adjustable inflation allows for total control of the level of exercise or support. Supports up to 400 pounds. "...The next day, my instinct was verified when I used the device after sitting in a course for more then 8 hours. Not accustomed to sitting for such long periods of time, my back was stiff and achy. I tried the Back Vitalizer -- 15 minutes sitting on the device and 15 minutes using the device as a lumbar support. I repeated this process several times during the day, and when I woke the next morning, I didnt feel a trace of stiffness in my back. During therapy, I use the device to increase proprioception, improve balance and alleviate pain. In just several months, the Back Vitalizer has become an integral part of my treatment plan for back pain and stiffness, and weak core muscles." Dan OConnor, PT, is the President of Sportho Physical & Aquatic Therapy in Chicago. The item can't be shipped to AF, AA, AC, AE, AM, AP in the Unite States.