The material of the ball: environmentally friendly rubber foam soft, the single weight of the ball is 82 gramsWeight: 110 gramsProduct size: ball diameter 60MM; headband length 680MM; width 38MMHead circumference: minimum adjustable head circumference 460MM, maximum adjustable head circumference 600MMElastic cord: 2MM10 core high elastic cordEnhance Reflexes, Agility, and Speed for adults and kids comes with a headband and training ball system that helps improve reactionary speed, tests your hand-eye coordination, and hones your punch skill tree.Comfort Fit Headband Trainer Offering a perfect fit for kids and adults at every skill level our reflexing punching ball system features a soft, breathable headband that quickly adjusts to fit your size for optimal training and efficiency.Universal Fitness, Sports, and Athletics Beyond boxing you can develop cat-like reflexes for MMA fighting, hand-to-hand combat, defense and ground tactics, Jiu Jitsu, Karate, and other forms of martial arts. Its even great for general exercise.