Features:1. Integrated BT chip, offers fast speed, stable connection, allows transmission of 10 m without obstacle.2. Compatible with mainstream devices with BT function, suitable for multi-platform, multi-system, and major brand mobile phones.3. Effectively block external noise, and real-time audio calibration can maintain a high-quality listening experience.4. The in-ear headphones are ergonomically designed to fit each ear perfectly. Perfect for exercise, running, sports and games.5. Button control, which is more convenient and accurate. You can easily switch songs, answer/reject phone call, volume up/down.Notice:Actual color may be slightly different from the image due to different monitor and light effect.Please allow 1-3cm deviation due to manual measurement.Description:Bluetooth-Compatible Version: V4.1Working range: barrier-free 10~15 metersWireless frequency: 2.402-2.480GHzTransmission power: Class2Battery capacity: 90mahPlaying time: 7-8 hours