Benefiting from all of the features of the 3M™ PELTOR™ FM Radio, the Alert adds extra protection by listening to the surrounding noise levels and adapting to what it hears. It attenuates loud noises and amplifies weak ones, protecting the wearer and making it possible for them to hear colleagues whilst protecting from harmful noise. Key Features: Easy to use volume control to adjust radio and level-dependent function. Automatically switches to mono for optimal listening in case of weak signals. Excellent bass sound. Radio never exceeds 82dB(A). Supplied with 3.5mm Stereo.