1. 8D surround sound, 5.0 dual-ear chip, large capacity, true wireless headset 2. Graphene bass diaphragm, HIFI high-frequency technology, 10MM dynamic speaker unit 3. Two connection methods: single / double free to use, single ear listening to enjoy alone, listening to HiFi stereo in both ears. 4. 5.0 automatic boot pairing, built-in active noise reduction IC, HD call. 5. 5.0 BT game without delay, the electric cabin can be used as a mobile phone bracket mobile phone emergency power supply, multi-function use. Product name: F9-5 Color: Black,white Wireless connection BT 5.0 Communication distance 10 meters (accessible environment) Headphone standby time about 150 hours Single earphone battery capacity 50mah Charging box battery capacity 2000mAh Charging box charging time about 2 hours Headphone charging time about 1.5 hours Control Button Yes Volume Control Yes Frequency Response Range 20-22000Hz Resistance 32Ω Automatic pairing: 1. Remove the left and right (LR) headphones from the charging case. The ear will automatically open and connect 2. Turn on the phone BT search and click on the main headset name to pair. 3. When used again, they will automatically connect to your BT device