BRAVEN 850 Portable Wireless Bluetooth Speaker [20 Hours Playtime] Built-In 8800 mAh Power Bank Charger - Silver The 8800mAh battery will play for up to 20 hours Transform the room into a concert hall with 20 watts of stunning audio Plug the charging cable for your phone or tablet into the speaker's USB port and get an extra boost of power Stream your music over Bluetooth by syncing with a compatible device Use the built-in noise cancelling mic to make and take calls wirelessly on your own, or in a group Stream your music over Bluetooth by syncing with a compatible device Transform the room into a concert hall with 20 watts of stunning audio Enhance your audio experience increased clarity and bass response by using SRS WOW HD technology