This Exercise Ball Base is designed to hold a stability exercise ball in place while you perform your favorite core exercises. The large surface and depth of the base lets you receive the benefits of an exercise ball while controlling the ball movement. Keeps exercise ball stable for various ball exercises. Can be used as a base for using an exercise ball as a chair. Slates in base allow for exercise tubing (sold separately) to be attached so you can perform additional exercises. Dimensions: 20"W x 4"H. Available in Black.