Do-All Outdoors Sound Soldier Quad Muffs are made with a durable, high-quality ABS plastic construction and Butyl rubber ear pads for maximum performance and all-day comfort. Each Sound Soldier Quad Muff features four omni-directional, wind-resistant, high-frequency microphones with durable iron gauze mic covers to enhance your hearing up to nine times. They are also equipped with independent volume controls with AFT (Adjustable Frequency Tuning). This system allows you to fine tune each set to your individual hearing needs as well as specific environments. These features plus their Sound Activated Compression for sounds above 85dB to protect the user from the harmful effects of muzzle blast, give you some of the finest hearing enhancement and protection on the market. Approzimately 200 hours of battery life. NRR 24dB.