BXO1017 Features: * Active back * Material: Breathable elastic * Support contains 6 concentric circle magnets * Ideal for back pain and allows more flexibility * Patented breathable material perfect for tennis or golf * Provides extra support * Magnetic fields: 6 * Gauss: 500 Per magnet * Small / Medium fits waist sizes 26"" - 35"" * Large / Extra Large fits waist sizes 36"" - 47"" * Proudly manufactured in the USA Dimensions: * Small / Medium dimensions: 6"" H x 32.5"" W x 0.25"" D * Large / Extra Large dimensions: 6"" H x 41"" W x 0.25"" D