The Everlast C3 100-Pound Foam Elite Heavy Bag is designed to provide professional level training for boxers. This heavy punching bag can also be used by individuals who box for fitness. The C3 (Contoured Closed-Cell Foam Technology) used in this boxing bag increases cushioning and force dispersion required by serious hitters, especially during heavy workouts. The high-density foam's closed-cells also reduce moisture transfer from the foam padding to keep your gloves dry during use. The Everlast C3 Foam Heavy Bag's custom filling of natural and synthetic fibers blended with sifted sand allow excellent shock absorption.