Combines the best of the stability ball and foam roller Versatile tool allows movement in two planes. This inflatable roller maximizes abdominal exercises to strengthen and tone obliques and core muscles. Adjustable firmness provides a stability challenge for kneeling, seated, or lying exercises. Not designed for standing exercises. Instructional poster included. Air pump sold separately. Color: Gray. Dimensions: 6" diameter x 30" L. Wt. 3 lbs.