The Caldwell E-Max Low Profile Electronic Hearing Protection hearing protection combines great circuitry with a low profile earcup that's ideal for shotgun shooters and action shooters. The two microphones in the E-Max amplify sounds below 85 decibels, which amplifies normal communication, range commands, and environmental sounds. Above 85 decibels, the microphones shut off for a split second to protect the shooter's hearing. Two microphones, one in each cup, give the user true stereo sound and allow the user to identify the directional source of a sound. These protection muffs include an integrated audio input jack allowing music to be played. They run on 2 AAA batteries (not included) and feature a 23 decibel noise reduction rating