switching between primary and secondary. pop-up window. Use the tap function. intelligent induction. HIFI voice that is clear. Lanyard and silicone case. The GB/T14471-2013 standard The earphone In-ear fit Details: Lightning Version 5.2 of the wireless connection protocol Distance: at least 10 meters Battery capacity: 33mAh Transmission frequency: 2.4GHz-2.48GHz 180-hour standby time Capacity of the charging case battery: 300mAh About six hours of music Talking time: roughly five hours About two hours for USB charging