Achieve old school training with new school technology with the Century Vinyl Black Medicine Balls. This medicine ball is filled with sand and provides an ideal way to add to your training and workout routines. Its outer shell is an easy-grip vinyl cover that provides a safe and durable surface. Build muscle and endurance with this quality medicine ball. Available in a variety of weights. About Century LLC Century's core belief is that martial arts can profoundly impact people's lives, and they want everyone to reap the lifetime benefits. In 1976, Century began by creating martial arts products, and has grown to become the largest supplier of martial arts products in the world. When the company moved to Midwest City, Oklahoma, in 1982, the original building provided 50,000 square feet to help the founders achieve their mission. Since then, the company has expanded to a 650,000 square foot facility, and also broadened its product offering to include yoga, boxing, MMA gear, and physical fitness equipment.