Aftershokz is the pioneer in bone conducting headphones. I absolutely love my Air for outdoor exercise, especially cycling. You can enjoy music and keep an open ear for road conditions at the same time. And it's very comfortable to wear over a long time because you don' need to put anything in your ear. I have been riding for some 4+hours rides with them without any problems. They also introduced some newer models that are worth checking out. Due to the nature of bone conducting, the sound quality isn't as good as traditional earbuds but I don't care too much about sound quality when exercising, and I think it's a small price to pay compared to the safety it brings.