Bose advanced technology automatically senses noise around you and adjusts the headset volume accordingly. In a loud environment, the volume increases so you can hear your call. When things quiet down, the volume decreases. Either way, the listening level remains constant. All the while, Bose TriPort acoustic structure ensures a natural voice quality, whatever the volume level. The person on the far end of the call hears you better, too. The Bose Bluetooth headset features an improved noise-rejecting microphone system that differentiates between your voice and background noise - even in windy environments. With technologies that accentuate voices over noise, the Bose Bluetooth headset allows for more natural-sounding conversations with fewer interruptions - at both ends of the line. The side-specific design of the Bose Bluetooth headset series 2 allows you to get the fit that's right for you. The curved design fits facial features, and the button placement on top and bottom allows the use of a natural pinching motion that won't dislodge the headset from your ear. And the soft StayHear silicone tip keeps the headset comfortably and securely in place. It distributes contact over a greater area inside the ear, avoiding known pressure points. The headset stays in your ear without being too tight - and without an ear hook. The Bose Bluetooth headset has separate buttons for power, volume and call send/end, all conveniently located on the top and bottom edges of the headset. Each action, from taking and ending calls to inserting or removing the headset, can be accomplished simply with one hand - important while you're driving or on the go. When you're not on a call, you can enjoy mobile media content through A2DP. The Bluetooth profile for streaming audio content lets you listen to turn-by-turn directions plus stored music, pod casts and other media on your smartphone