Voi is composed of high-end Bluetooth headset and lithium polymer power bank of 5,200 mAh. The headset with Bluetooth 4.0 version lengthens standby time and supports NFC matching and dual microphone noise reduction. The A2DP technology allows wireless callings and music, game and video entertainment. It has memories for eight devices and connects to two devices at a time. Unique human engineering earpiece design provides wearing on either ear. The volume can be adjusted with six cycles. Charge Voi by simply putting it into power bank magnetic slot. The headset is functional while charging. With an extra USB outlet can charge two devices at a time.