Aftershokz Sportz 2 AS320 Open Ear Sports Headphones AfterShokz Sportz M2 headphones sit comfortably in front of the (not in or over the ear) and utilize patent pending bone conduction technology to deliver stereophonic sound through the listener's cheekbones to the inner ear Open ear design enables anyone participating in an activity - jogging, biking, skateboarding, hiking, skiing - to make/take phone calls and stay connected to both what they are listening to and the outside world You can hear important sounds, including noises such as oncoming traffic, car horns, ambulances or other warning noises, potentially preventing accidents that can be caused by headphones and earbuds blocking out these sounds. More comfortable and stable than earbuds or traditional headphones, especially when used over extended periods of time Reflective silver safety strip on back of headband for added visibility and safety during activities