Product Description Features: TWS earphone 2019 new stereo headphones i9s / bluetooth sport/bluetooth V5.0 wireless earphone audio earphone/ Specifications: 1. Chipset: Jieliï¼? 2. Blutooth version: Blutooth V5.0ï¼? 3. Blutooth band: 2.4GHzï¼? 4. Battery: box battery is 300mah, earphone battery is 40mahï¼? 5. Channel mode: 2.0 real stereo; 6. Blutooth distance: 10 metersï¼? 7. Frequency response: 20-20000Hzï¼? 8. Operating voltage range: 3.0V-4.2Vï¼? 9. Speaker: real copper ring 10 / frequency response 20-16HZï¼? 10.Distortion rate: THD