Bone conducting models............end topic there. If you're outdoors running or cycling and need to hear your surroundings, it keeps the ears open. Then you can pop in the included ear plugs for max indoors isolation.

I love my Aftershox. Not the absolute best sound quality, but that's a small compromise for open ear use and good rugged use for sport.

The person asked for tips here, so there it is. I run and bike in silence, but.........if someone doesn't then that's my recommendation.

I am currently using the Jabra Active Elite 75t --with Wind Blox--and I am pretty happy with them. They have hear through feature which lets you be much more cognizant of your surroundings. I like the quality and fit, plus I sweat a lot so its reassuring that they are waterproof.