Walker's Game Ear Digital HD Power Hearing Enhancement Systemment Outdoor power hearing enhancement system increases your hearing up to 7 times Protects ears from the damaging effects of loud noises Sound-activated compression circuit with 29 dB noise reduction rating 48 dB of total power; includes sound tube, earplug, and 3 batteries Behind-the-ear main unit weighs less than 1/4 ounce; carrying case