The Howard Leight Impact Sport Electronic Earmuff in TEAL amplifies sound while automatically blocking hazardous noise. Directionally placed stereo microphones amplify sound for more natural hearing while blocking harmful impulsive noise over 82dB. Comfortable for extended wear with a contemporary and adjustable fit. The low-profile earcup design includes a cut-out allowing full clearance for firearm stocks Allows you to connect to any audio source, such as MP3, CD or scanners. Noise Reduction Rating 22 Automatic 4 hour shut-off extends the battery life to 350 hours One volume control knob allows easy access to change the level of volume in each ear Easily store the Impact Sport in your range bag because of its compact folding design Package includes ear muff, 2 AAA batteries and AUX input cord.