Features: Multifunction: Equipped with features of stereo BT, TF card reading, AUX in, FM radio, and hands-free call with Microphone. BT Connection: BT4.2 ensures strong transmission signal, delivering high-fidelity stereo music. Also supports BT hands-free call. Line-in Function: Connect to the music players (such as, MP3 / MP4, etc) without BT function via the included 3.5mm cable. Long Battery Life: Built-in 300mAh rechargeable battery lasts up to 6 hours of working time and 60 hours of standby time per charge cycle. Ergonomic Design: Foldable and adjustable headband length, soft leather ear cushion, comfortable to wear and easy for storage.