1. Adopt non-in-ear design to always perceive ambient sound. 2. Ergonomic ear design, comfortable to wear. 3. Ear-hook structure, more stable and fit. 4. Stereo sound quality, HD calls. 5. IPX5 waterproof, water-resistant and sweat-resistant. 6. Parameters: Material: PC+ABS Frequency response range: 50Hz-10kHz Bluetooth version: AD7003D4 V5.4, distance: less than or equal to 10M Listening to music and talking time: about 6H Earphone battery capacity: DC 3.7V/50mAh Box battery capacity: DC 3.7V/400mAh Charging interface: Type-C