Product name: Redmi Buds 4 Product model no.: M2137E1 Earbud input parameters: 5V 100mA Charging case input parameters: 5V 450mA Wireless connection: Bluetooth 5.2 Bluetooth protocol HSP HFP A2DP AVRCP Operating distance: 10m open space free of obstacles Single earbud net weight: Approx. 4.5g Total weight including charging case: Approx. 55g Charging port: Type C Speaker impedance: 16 15percent