A reaction ball is a small rubber ball covered with lumps that help to create erratic bounces when the ball hits a surface. Reaction balls are used to develop better reaction speed, agility, footwork, hand-eye coordination, lateral movement and overall ??quickness??. It can be used by sportsmen, sportswomen and martial artists. The ball can be used for training alone or with partners. These reaction balls are made of high density hard rubber. The size is roughly 60mm largest diameter.