Two boards in one - rocker and wobble. Improves balance, stimulates muscle activity and quickens reflexes. wide platform accomodates even the largest patient. center ball is 4" in height for agressive training. Model 2000BA includes extra 3" center ball to accomodate the beginner patient yet allows for progression to the 4" ball. Board Dimensions are 15"L x 7"W. Can support up to 500 lbs. Latex free.