SureFire EarPro EP3 Sonic Defenders, In Ear Hearing Protection, Small, One Pair

EP3 Sonic Defenders protect your hearing, without interfering with your ability to hear routine sounds and conversation. Safe sound levels are allowed to pass through while potentially harmful noises (above 80dB) are reduced via a proprietary design that incorporates the patented Hocks Noise Braker filter. When even more hearing protection is required-without the need to hear routine sounds or conversations-Sound Defenders' attached stoppers can be inserted. The right/left color-coded Sonic Defenders are made from a soft, hypoallergenic polymer and ergonomically shaped, with a multi-flanged stem, providing a comfortable all-day fit. And their low-profile design means they can be worn while wearing a helmet or mask or while using a phone or headset. EP3 Sonic Defenders are double-flanged for a proper fit for most people.

Owner Reviews, Ratings, Comments and Criticism
If you understand frequencies and the dB scale, look at the breakdown of noise reduction levels over the frequency spectrum and see how these things work, it's nifty.