The fascia ball is made of rubber material, which is safe, non-toxic, tasteless and long time to use. The fascia ball can release and eliminate muscle knots and tension, relieve sore and tight muscles to and revitalize all areas of the body. Simply lean on the massage ball and use your own body weight and gravity to relieve muscle knots and tension. Perfect for use while sitting on any chair, laying in bed, on the floor, or on a yoga mat. Use them , at , or at the gym. The fascia ball is small, portable and easy to bring along on any trip. Specifications: Colour:yellow Material:rubber Size:Diameter: 63.5mm Package Contents: 1 * massage ball Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.