Everlast punching 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) this Everlast heavy bag increases cushioning and force dispersion required by serious hitters, especially during intense workouts. The high-density closed-cells also reduce moisture transfer from the foam padding to keep your gloves dry during use very goof to use