The Sonetics APX377 wireless headset protects you from dangerous noise levels while enhancing all other audio to a comfortable listening level. Extend team communication up to 1,600 feet (line-of-sight). Stereo Listen-Through protects your hearing when you need to hear warnings and alarms or have a face-to-face conversation. Connect a two-way radio or MP3 player via direct-wire inputs. Engineered and tested for rugged durability in extreme environments, the APX377 improves team communication no matter where you work.