[GOOD MATERIAL: The ball is made of quality material sturdy and the string is highly elastic and wearable ADJUSTABLE HEADBAND: The headband is stretchy and adjustable with hook&loop the small ring on the headband is for hanging string WILD APPLICATION: Lightweight and portable suitable for many places like room garden park etc IMPROVE SPEED & SENSITIVITY: Easy to use the harder you kick the faster the ball comes back. It can help to improve speed and sensitivity GOOD TOOLS: Great accessories for boxing training]