Purchased to improve dynamic visual acuity. Used a few times and stored at home. No returns. Shipping method may be changed from Yu-Yu to Raku-Raku (or vice versa). If you have a preference, please comment when purchasing. In either case, it will be sent via anonymous delivery. Improves athletic ability, concentration. Headband type. Wear for training. Improves dynamic visual acuity, improves concentration, accuracy, hitting sense. Training. Outdoors, indoors, small spaces. Aerobic exercise. Boxing, kickboxing, Muay Thai, mixed martial arts, baseball, basketball, soccer, tennis, badminton, table tennis.