Features: 1. Light weight、 length adjustable hinges、 comfortable to wear. 2. Build-in rechargeable li-battery、 charge via USB cable for 2~3 hours. 3. Standby time up to 250 hours、 can work for about 10 hours continuously. 4. Built-in microphone、 voice prompt power on\/off and pairing、 support voice dial for iPhone. 5. Enhanced noise reduction、 good choice for listening music、 watching movie、 talking on the phone、 etc. 6. Multifunctional key allows you power on\/off、 answer\/hang up\/reject\/redial the last number、 pause and play. 7. Bluetooth 4.1+ EDR、 support HSP\/HFP\/A2DP\/AVRCP、 connect two Bluetooth equipments at the same time. 8. Wireless Bluetooth headset、 compatible with Bluetooth enabled devices、 such as iPhone、 iPad、 HTC、 Lenovo、 Samsung、 Tablet PC、 etc.     How to use:     Power on: keep pressing Multifunctional key until you see the blue LED shine.   Power off: keep pressing Multifunctional key until you see the red LED shine.     Pairing:     First、 please make sure the headset is power off and the Bluetooth devices is within 10m.   Second、 press Multifunctional key for 5-6 seconds until blue and red LED shine by turn.   Third、 activate Bluetooth of the device you want to pair、 search and select "BH-02" in the Bluetooth list.   Fourth、 according to indication、 input the code "0000" and confirm.   After pairing succeed、 the blue LED of the headset shines twice or three times every 4 seconds. Specifications:          General Specification             Brand         Acarte             Model         BH-23             Color         Black、 White、 Red、 Blue、 Orange、 Pink             Wearing Type         Headset             Product Weight         183g             Dimensions         14.5*10*3cm           Technical Parameters             Built-in lithium battery         180mAh             Driver Unit         30mm             Impedance         32Ω             Frequency Response         20-20、000Hz             Standby time         250 hours             talking time         8~10hours             Charging time         2~3 hours             Input voltage         DC 5V             Bluetooth Version         4.1             Bluetooth Profiles         HSP \/ HFP \/ A2DP \/ AVRCP             Transmission Range         10m    Package  Included:                   1 × Acarte BH-23 Headphone             1 × Charging cable             1 × English manual