Total Control Atomic Training Ball (Multi Pack) 
Total Control Atomic Training Ball (Multi Pack) Develop strength and extension through the hitting zone while providing instant feedback for the hitter. Perfectly weighted by design, Total Control Balls are used for optimum resistance to develop slowtwitch and fasttwitch muscles. Pure strength development for core and upper body. Used for side toss tee work only. Works the Core, Upper Body Hips. Features Size: 5.2" in Diameter Weight: 900 grams (31.7 oz.) Instant Feedback Limited Space Required Perfect Weighted Design Long Lasting and Washable Soft Toss Without Net Safe for All Bats No Glove Required