Features: 1. listening to the song correct, support songs and call, 2. remind call number, the last call back, all intelligent Chinese and English voice prompts, boot, pair, shut down the phone power will be low voice prompts; 3. Power capacity will show on your Iphone, you can see the power situation anytime, do not worry about the electricity ,make your life without worry; 4. One to two connections, can be connected to two mobile phones at the same time 5. Bluetooth headset connected to the phone after the shutdown  , and then open the Bluetooth headset will connect back to the phone  automatically  , more convenient; 6. Intelligent compatibility: support all Bluetooth mobile phone, tablet, notebook, singing it, QQ music, movies, etc., universal all mobile phone Specification: 1. Driver: 15mm 2. Impedance: 32 OHM 3. Bluetooth version: Bluetooth v5.0 + EDR 4. Bluetooth use band: 2.4GHz 5. Power level: CLASS II 6. Output power: 30mW 7. Bluetooth distance: 10 meters barrier 8. Frequency response: 20-20000Hz 9. Operating voltage range: 3.0V-4.2V 10. Mic sensitivity: -42dB 11. With A2DP / AVRCP high quality stereo audio transmission and remote control protocol 12. Powerful noise de-noising circuit (active noise reduction) 13. switch between Chinese and English (boot does not connect Bluetooth state, press the switch 2 times, hear the tone switch successfully) 14. Talk time is about 2-3 hours 15. music time about 1.5-2 hours 16. Standby time is about 100 hours Note: This product does not have a retail package box! ! ! Package Includes: 2 x i7s tws bluetooth earphones (left and right earphones) 1 x Charging box 1 x USB Charging Cable 1 x User Manual