The Howard Leight Impact Sport Bolt Electronic Shooting Earmuff features all new digital compression circuitry with a lightning-fast .5 MS (millisecond) attack time (250X faster than our classic Impact Sport model). This provides instant hearing protection that doesn't leave you in silence afterward. The attack time is the interval between when the sound goes above safe 82 dB hearing levels, like when a shot is fired, and when the earmuff reacts to lower the sound to a safe level. This is essential for range shooting, where constant gunshot noise can fatigue your ears. The .5 MS attack time also keeps you connected to your shooting environment by eliminating sound-clipping (the inadvertent blocking of ambient sound after a gunshot). This is crucial for hearing range commands or simply conversing with fellow shooters. Recessed microphones in each earcup serve to reduce wind noise, while boosting range commands or quiet animal sounds up to 5X. The microphones are also directional so you know where the sound is coming from (a real benefit for tracking prey). From a design standpoint, the low profile earcup features an indented cutout that allows your cheek to press flush to the gunstock without breaking the seal of the ear cushion. The leatherette headband is padded for comfort, and adjustable for a secure fit. Connectivity is also built-in, with an AUX input and 3.5 mm cord facilitating hookup for MP3 players, scanners etc. Two AAA batteries (included) deliver approximately 150 hours of usage, and the four-hour auto shut-off prevents needless draining. The Impact Sport Bolt Shooting Earmuff features a Noise Reduction Rating of 22 for ear protection. All Howard Leight earmuffs and safety eyewear are compatible for use with each other..