Bluetooth 5.0 Technology: ensures lower battery consumption, and gives you stable, swift connections. HD Stereo Sound quality: our built-in 13mm speaker drivers provide you with rich music and clear phone calls. Automatic Pairing and Switching: open your case cover and your earbuds will automatically connect to your device, both earbuds can also work independently. Enjoy lag-free music anytime no matter how you wear your earbuds. 30 hours Battery Life: get a guaranteed 4-5 hours playing time on one full charge and an additional 25 hours from the 500mAh Charging case. Ergonomically Designed: with a single earbud only weighing 4.5G/0.16oz and designed to fit, your wireless earphones will sit perfectly in your ears and won't fall out during exercise.