Ausdom Wirelss Bluetooth Sports Headphone In-ear Earbuds Ear-hook Earphone with Built-in Microphone (S04) Bluetooth 4.1 high-quality and lower power-consumption chip In-ear earplug design & ear-hook design, reduces outside noise to help you focus. Durable Strong Power -- Over 5 hours of continuous calling and playing time, 180 hours standby time. Drive-by-wire function make it more easy to control the voice volume and music playing Build-in microphone and hands-free, sweat- and water-resistant design for increased durability