3M 1270 Uses: Improve sleep, concentrate, protect hearing and so on. Is your home, dormitory, self-study classrooms, travel boat plane travel, factories, construction sites, downtown areas from noise interference is a good helper, is your healthy new life good partner. 3M 1270 Efficacy: Noise reduction (NRR) 31 dB, bullet-type profile design, smooth surface, the anti-fouling treatment, wearing health, safety, soft and comfortable, sound insulation is good, waterproof into the ears, can be used in swimming.