National rubber udyog's specifications  of  earplug 100% silicone material can reduce 28 db non-stick,easy to clean ear plug usage: to reduce noise, concentration, hearing conservation, etc. , it is a good helper from the noise when you are at home, dormitory, classrooms, airplanes, ships, factories, construction sites, etc. Can be used as swimming earplugs. Free to curl, easy to carry, save space. Effects: noise value (nrr) 25 db, a christmas tree-shaped contour design, by the anti-fouling treatment, can be cleaned with belt health, safety, soft, comfortable, sound good effect.