U&I UiTWS 4554 Twins True Wireless Stereo With Mic For All Smartphones – Happy Series

Bluetooth Version : 5 . 0+EDR
Power Input : DC 5V
Earphone Working Time : About 4-6 hours
Earphone Charging Time About 1 hours
Charge Time : About 3-4hours
Earphone battery capacity : 25mAh
Charging Case battery capacity : 250mAh
Support Protocol : HSP / HFP / A2DP / AVRCP
Frequency response : 2.40Hz