The PH-16 is a dual-sided monaural headset with noise-canceling dynamic microphone. It fits under a helmet and has an EPA rated NRR of 24dB. The dynamic receivers have special mounting which resist shock, vibration and acoustic feedback. The PH-16 ear cups are foam lined for added noise attenuation. The vented, foam-filled ear cushions combine comfort with good acoustic seal. For convenience and economy, the receivers and ear cushions are field repairable. Each headset features an adjustable flexible boom for optimum microphone placement.