Caldwell E-Max Electronic Hearing Protection. The two microphones in the Caldwell E-Max Electronic Hearing Protection 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. The Caldwell E-Max Low Profile Electronic Hearing Protection has two microphones - one in each cup that gives the user true stereo sound and allow the user to identify the directional source of a sound. Specifications for Caldwell E-Max Electronic Hearing Protections: Manufacturer: Caldwell Color: Black/Green Quantity: 1 Pair Battery Type: AAA Battery Quantity: 2 Additional Features: Over the Head Condition: New Features of Caldwell E-Max Electronic Hearing Protections 2 NRR Dual microphones Package Contents: Caldwell E-Max Electronic Hearing Protection 497700 or Caldwell E-Max Low Profile Electronic Hearing Protection 487557 Caldwell E-Max Electronic Hearing Protection 497700