1 x Premium Sound Amplifier Main Unit. 💡 BUY MORE, SAVE MORE! Sound Gain: ≥30dB +/- 5dB. Fits securely and comfortably behind either the left or right ear. Advanced Noise Reduction (≤28dB): Filters out distracting background noise, allowing you to focus effortlessly on conversations, TV shows, and the natural world around you.