Back on Track Back Brace Double Layer Back on Track's newest model that may provide even more support that the regular back brace because of the extra elastic straps on each side that allow you to adjust the tightness of the brace. The state of the art Welltex fabric works reflects your natural body warmth and creates a soothing far infrared thermal warmth--may be a welcome relief for tight lower back muscles. Measure around the waist for correct sizing. Refer to size chart. Machine washable up to 86 F or 30 C. Use normal detergents that do not contain bleach or fabric softeners. Air dry only, do not tumble dry. Back on Track products are not to be compared with magnetic therapy. Features: May provide soothing support for tight lower back muscles State of the art Welltex fabric Reflects your natural body warmth Elastic straps to adjust the tightness of the brace Machine washable