We specifically designed it to be much lighter and softer than the tennis ball, so it is grove-free, and everyone can enjoy it without any worries about hitting yourself in the faces, eyes, noses, and fists as well, it's much safer. It can help train your reaction, agility, punching speed, fight skill and hand eye coordination while providing an interesting workout. Lifting weights and long hours on the Gym bike is not the only way to get fit! In fact, Fight Ball might be even better and far more compelling. The unpredictability of the rebounding ball, coupled with the intensity of your punches will burn out your arms, chest, shoulders and upper back, perfect for calorie burning and conditioning. Also, it's very addicting. You don't have to go to a gym, strap the headband on, have fun and burn your body within 15-20 minutes! Perfect for work breaks or school breaks or even for the beach and the park, this focus punching bag will burn many calories and help you get fit.