To improve sleep, concentrate, hearing protection and so on. Are you at home, bedroom, self-study classrooms, car boat airplane travel, factories, construction sites, etc. from downtown noise is a good helper. Is a good partner for your healthy new life, and it is essential that you look at the F1 race. Summer swim earplugs necessary
Smooth surface, the antifouling treatment, wearing health, safety, soft and comfortable, good sound insulation.