CoreX Wall Ball/Medicine Ball 12, 14, 16, 18, 20, 25 Lbs. The CoreX Wall Ball is a must have for functional fitness training. Tossing and catching exercises are terrific for developing strength, core stability as well practicing sporting moves. Used as a medicine ball, an array of lifting and twisting exercises are ideal for rehabilitation needs. Each ball has a 14 diameter and is weight color coded for ease of identification. Six weights are available (LBS): 12, 14, 16, 18, 20 and 25. The CoreX wall ball is filled with rubber pellets and is encased by cotton batting. This is considered the optimal fill, as the rubber pellets absorb force, help maintain ball shape and weight distribution  unlike sand filled wall balls. The cotton batting provides cushioning that minimizes injury risk and retards bouncing. The CoreX wall ball is covered with thick, synthetic leather, providing tremendous tactile feel and durability. This material is designed to outlast thinner vinyl skinned wall balls. Redundant stitching is used throughout construction for added strength and longevity. The balls closing seam, is criss crossed laced for optimum securement. End loops enable hanged storage.