Charging case (15 hours): True wireless headphones with 20 hours running time (5 hours per charge of the headphones and 15 hours with the charging case) Stereo calls: hands-free headset with built-in microphone for making Stereo calls without worrying about noise Charging case (15 hours): True Wireless headphones with 20 hours of autonomy (5 hours for each charge of the headphones and an additional 15 hours in the charging case