The Flex BeltĀ® is the first Ab Belt Toning system cleared by the FDA for Toning, Firming and Strengthening the stomach muscles. With The Flex BeltĀ®, you can train your abs even if you're too busy or too tired for a traditional workout. Just slip on the comfortable toning ab belt and the clinically demonstrated, patented medical-grade technology stimulates the nerves that make your muscles contract and relax. As a result, you get an effective abdominal workout that targets all the muscles in your abdomen - all in just 30 minutes a day.