The ATH-C200BT in-ear headphones offer excellent Bluetooth wireless sound quality at an exceptional value. These “open” style earbuds feature powerful 12 mm drivers coupled with specially designed sound tubes that control airflow to deliver full-range audio with enhanced low-frequency performance. Yet the open design also allows some ambient noise to get through so you won’t lose awareness of your surroundings. Silicon housings ensure a secure, comfortable fit.The headphones feature an in-line mic and controls, allowing you to answer calls, adjust volume and control music playback on smartphones and other devices. The ATH-C200BT’s design conveniently situates the mic and controls for easy access and places the battery case on the upper back where, if desired, it can be attached to your shirt collar with the included clip. The internal battery powers the headphones for up to 9 hours (200 hours standby) and can be recharged with the included 30 cm (12") USB charging cable.The Bluetooth word mark and logos are owned by Bluetooth SIG, Inc. and any use of such marks by Audio-Technica Corporation is under license. Other trademarks and trade names are those of their respective owners.