EP7 Sonic Defenders Ultra protect your hearing without interfering with your ability to hear routine sounds or conversations. Their foam-tipped stem design, featuring soft memory-foam Comply Canal Tips, fits most people and provides a Noise Reduction Rating (NRR) of 28dB. Sounds, at safe levels, are allowed to pass through into the ear canal, while potentially harmful noises (above 85dB) are reduced via a proprietary design that incorporates a special noise-reducing filter. EP7s include attached filter caps, which can be inserted for additional protection and blocking out lower-level noise, like that heard on a plane, in situations where hearing ambient sounds or conversations isn& Mfg: Surefire