Chipset: Pixart 1606  Support: A2DP1.3/HFP1.6/HSP1.2/AVRCP1.6                                                 Bluetooth version: 5.0v  Speaker size:Φ10mm  Impedance: 16Ω ± 15%  Frequency range: 20Hz-20kHz   Effective range:up to 10 meters  Earbud battery capacity: 2*40mAh  Bluetooth work time: up to 4.5 hours   Charging case battery capacity:300mAh  Earbud charging time:~40mins    Charging case charging time: ~ 1.5 hours   Charging port: Type-C USB   Input rating : DC5.0V  Sensitivity: 95+/-3dB   Work voltage: 3.7V  Microphone sensitivity: 43+/-3  MOQ per customized color 2000pcs