1. Using ergonomic headwear design, fits the head shape, suitable for most people to wear, comfortable wearing feeling 2. 40mm large moving coil unit, combined with large ear structure, low frequency shocking and powerful performance, very , and the bass is more powerful 3. Using a of Bluetooth 5.1 technology, lower power consumption than Bluetooth 4.2, faster transmission, strong anti-interference, and more stable signal 4. The use of wire drawing telescopic head beam design strengthens the toughness between the earphone and the head beam. 5. A of modes to choose, support Bluetooth/AUX wired/card playback Product name: Bluetooth headset Bluetooth version: Bluetooth 5.1+ Receiving distance: barrier-free 15m Speaker size: 40mm Frequency response: 20Hz-20KHz Impedance: 30 Battery capacity: 650 mAh Charging time: 2-3 hours Life time: 24 hours (maximum volume) Standby time: 300 hours Channel: stereo How to use: head-mounted Compatible with a of Bluetooth devices: support IOS/Android/tablet/computer/MP4 Function: battery display, call function, colorful breathing light size:18x19x7.5cm Material:ABS colour:Red Package Contents: 1 * Bluetooth headset 1 * charging cable 1 * audio cable Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.