PH-100AC ANR aviation headset with Active Noise Reduction, Clear Hear performance audio speakers, dual volume control stereo, and easy access AA battery box with mono switch. Comfortable half Gel half foam ear seals;Adjustable spring steel headband;Clear Hear ANR audio technology blocking out the background noise;All new designed noise cancelling microphone and wind block foam mic muff.Pilots and flight instructors will enjoy the PH-100AC ANR aviation headset Brought all day comfort.