BC200 bone conduction headphone, Bluetooth V5.2, 7-8H playtim e from Shenzhen Winto technology Co., ltd 1.Bluetooth Version: V5.2 2.Chipset:BK3288 3.Bluetooth Profiles: A2DPv1.3 AVRCPv1.6  HFPv1.7 4.Decoder: SBC, AAC 5.Transmission Distance: 10m 6.Playing Time:7H(80% volume) 7.Charging Time:2H 8.Standby Time: 200H (w/bluetooth connected); 9. Battery: 3.7V/180mAh 10.Frequency Range:20Hz~20KHz 11.Sensitivity:83.5 ±3dB 12.Impedance:8 13.Dimension:140x112x43.5mm 14.Weight:around 32g 15.Color:Black,Blue,Red 16.Speaker type: Bone conduction transducers 17.Speaker size: 16.2x5mm 18. Material: Hypothermia Titanium alloy &PC & Silicon 19.Voice assistant: Compatible with Siri & Google assistant 20. Waterproof: IPX7