By blocking out loud, harmful noises at any moment while simultaneously enhancing environmental sounds and voices, our Apollo Electronic Sound Suppressors provide excellent audio quality along with a noise reduction rating of 24dB. Passive Sound Dampening - 24dB NRR Active Electronic Sound Compression Compact Collapsible Design Includes Adaptive Cool Gel Ear Pads 1x American Flag Patch 1x Savior Writable ID Patch 2x AAA Energizer Batteries U.S. Patent No. D1055397