This eye-catching exercise ball is covered with hundreds of small bumps that make regular exercise ball activities even more stimulating! Sitting on the ball strengthens core muscles, body awareness, balance and attention. Perfect therapy ball for those who need to awaken their sensory system, and sensory-seekers who crave additional sensory stimulation. Stimulating bumps encourage tactile exploration and great for active seating, exercise or play. 28" diameter. Ages 3 and up.