Chip: AD6983D2 Bluetooth version: V5.3 Earphone battery: 25mAh Charging compartment battery: 300mAh Music duration: approximately 4 hours (80% volume) Charging time: approximately 1.5 hours Standby time: 120 days of standby time Speaker specification: Full frequency speaker with a diameter of Φ 13mm@32 ohm Transmission distance: ≥ 10 meters Material: ABS+PC Bluetooth operating frequency: 2.402GHz-2.480GHz