The Ooof ball takes medicine ball training beyond its normal applications. The OOOF Ball is a very versatile product; can be used in strength and conditioning programs for sport specific skills, rehabilitative exercises to promote balance, strength and grace in movement, cross training fitness or just for fun. How does the Ooof ball compare to other medicine balls? Some balls require inflation of air. Many times the balls do not stay fully inflated during use, decreasing their effectiveness and function. An optional added piece of equipment, the air pump is also required with these balls. Some balls are weighted with sand and/or sawdust. These weights can shift or if the covering breaks, you've got a mess to clean up and no way to fix the ball. Some balls don't bounce, decreasing the ways in which they can be used. An added piece of equipment such as a rebounder board may be required. The OOOF Ball is 100% Latex FREE. As you know, latex allergies can be life threatening and anyone can develop an allergy to latex at any time. Many of the medicine balls on the market have latex as an integral component or have a latex outer shell. Availablie sizes ranging from 2 to 9 lbs.