This is a Twins wireless earpiece Bluetooth with charging box that serve as its power bank and can charge the bluetooth even when there is no light.1. listening to the song correct, support songs and call2. Caller ID, the last call back, all intelligent Chinese and English voice prompts3. Apple phone power display, you can always watch the headset power situation, do not worry about the headset no electricity to make your life worry;4. One to two connections, can be connected to two mobile phones;5. Convenience: Bluetooth headset will automatically connected back to the phone every time it power back after being shutdownItem type: Bluetooth HeadphoneBluetooth version: Bluetooth v4.2 + EDRSize: 5 * 2 * 1.5cmColor: As shownMic sensitivity: -42dBFrequency response: 20-20000HzOperating voltage range: 3.0V-4.2VDriver: 15mmBluetooth distance: 12 metersPower level: Class IIOutput power: 30MWBluetooth use band: 2.4GHzImpedance: 32 OHM.