The Ab Wheel Plus with instructiona DVD is great for strengthening your core muscles to help firm, tighten and flatten your abs to get the six-pack you've always wanted. Durable TPR wheel with PVC hand grips and 2 kinds of steel rod clamps. Start on both knees with the ab wheel just in front of the body on the floor. Tighten the core with arms fully extended and slowly roll the wheel forward until your body is parallel to the ground. Squeeze your core tight, without your back arching, and roll yourself back to the starting position and repeat