Caldwell E-Max Low Profile Electronic 23 NRR Hearing Protection with Sound Amplification and Adjustable Earmuffs for Shooting, Hunting and Range, Green COMFORTABLE: Padded headband and adjustable cushioned ear cups allows for a snug fit to ensure proper noise cancellation and protection. The low-profile design allows for a closer fit against your rifle for more accuracy and comfort HEARING PROTECTION: 23 NRR (Noise Reduction Rating) amplifies low sounds (below 85dB) and compresses high noises (above 85dB) to create the perfect range experience CONVENIENT: The lightweight design is impact resistant and folds compact for transport EASE OF USE: Runs on 2 AAA Batteries (not included) with adjustable volume control and an audio jack for a phone or MP3 player