Enjoy your tunes like never before when you use these Synergy true wireless earbuds. These electronic accessories are designed with built-in environmental noise cancellation, with dual microphones for hand-free operation, for 4.5 hours of playback at max volume on a single charge, and Bluetooth technology that will automatically pair to your phone once on. They come inside of a 1.01" x 2.28" x 1.85" rechargeable case that charges these earbuds as they're inside. Once the case is opened, these wireless earbuds will automatically power on and sync with each other for immediate listening. Go to the beat of your own drum when you promote with these Synergy auto-pair earbuds.