Aftershokz AS321-E Sportz M2 Open Ear Sports Headphones with Inline Microphone - Black In-line microphone to make/take phone calls Sit comfortably in front of (not in or over) the ear, using patent pending bone conduction technology to deliver stereophonic sound to the inner ear Open ear design lets you make/take phone calls and stay connected to your music and the outside world - even when skiing, running, biking etc. Hear important sounds, including oncoming traffic, car horns, ambulances or other warning noises, potentially preventing accidents More comfortable and stable than earbuds or traditional headphones, especially when used over extended periods of time Connectivity technology : WIred