Skillbuilders Rolls are ideal for physical therapy departments, rehab clinic, gyms, home use, and like wedges, they are used to foster exercise therapy and general positioning. As an example, the roll can be placed under the knee to allow weighted ankle lifts. Skillbuilders Rolls are soft, but yet, the supportive molded foam rolls offer a stable surface for beginners unlike traditional firm rolls. The Rolls have a solid core to help prevent “bottoming out” (except 4″-diameter Rolls).The thick, waterproof polyurethane coating is seam-free and allows for easy cleaning and has an attached handle for the convenience of hanging or carrying. The heavy-duty rolls will give you years of use. Positioning Roll – 10″ X 36″.