Caldwell E-Max Electronic Ear MuffsThe Caldwell E Max Electronic Earmuffs combines great circuitry with a standard earcup for better protection. 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. Ear Cup Width: 2. 25" Batteries: 2 AAA (not included) NRR: 25 dB Cutoff: 85dB CE Certified: Yes