The 3M™ PELTOR™ ALERT™ Headset helps protect you from potentially harmful workplace noise while at the same time provide the enjoyment of listening to the built in FM-radio. The level-dependent function for environmental listening allows sounds to be heard at a level below 82dB to increase your ability to communicate with nearby colleagues, as well as to hear warning signals, approaching vehicles, or sounds in machines and processes. The 3.5 mm listen only stereo input (limited to 82 dB) connects to external devices (e.g. mobile phone, two-way radio, MP3 player) via the included 3.5 mm cable.