Bluetooth version: 5.0 Bluetooth Class(1/II):Class II Bluetooth Profile:A2DP,AVRCP,HFP,HSP Speaker Type: Bone conduction technology speaker, 1w dual speaker Receiving Sensitivity:88dBm Impedance: 8Ω MIC:-42db MEMS MIC Frequency range:20‐20KHz Play time: 4H Standby time: 10 days Transmit range: 10M (33feets) Battery:120mAh Power battery Charging port: micro USB Weight: 26g Sizes: 144x116x42mm