1) BEST HD TWS STEREO MUSIC: Harmonics Twins gives you true freedom from cables dangling from your head and gives smooth experience of listening to music. 2) LATEST BLUETOOTH 5.0: It uses latest and most power efficient Bluetooth 5.0 BLE low energy which does not drain the battery of your phone quickly. 3) ACTIVE-SMART CASE: The case is pocket-friendly sized have a battery size of 43 mAh and the case has the capacity of 380mAh.