Stretches ligaments and muscles back into correct form. Promotes disc lubrication & joint nutrition. * Rocking mechanism allows you to exercise abdominal and pelvic muscles while lower spine is stretched by elliptical inflation. * One size fits all, including tall persons with a torso length of up to 38 inches from head to waist. * Easy to clean leatherette comfort pad attaches both exercisers and conveniently folds and locks together for easy travel. * 1 year parts and labor warranty.