The Howard Leight Impact Sport Electronic Earmuff in BLACK amplifies sound while automatically blocking hazardous noise. Directionally placed stereo microphones amplify sound for more natural hearing while blocking harmful impulsive noise over 82dB. The Impact Sport earmuffs are 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. The external audio jack 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. You can easily store the Impact Sport in your range bag because of its compact folding design. Package includes earmuff 2 AAA batteries and AUX input cord.