Product parametersProduct namei9 S TW S Mini Bluetooth headphones  Battery capacity and usage time instructionsTalk time is about 4-5 hours(with r box)Talk time is about 1.2 hours (USE ALONE):Music time about 2-3 hours(with r box)Music time about 1 hours(USE ALONE)Standby time is about 100 hoursThe charging time is about 60 minutesCharging compartmentCharging time 60 minutes Charging voltage 5V Endurance 4-5 timesAudioparametersFrequency response range 20HZ-20KHZMitou sensitivity: -42dBTransmission distanceTransmission distance 15-20mTransmission frequency 2.4GHZ bandBluetooth versionDual mode Bluetooth V5.0+EDR, ultra low power consumptionsupporting agreementA2DP1.3/HFP1.6/HSP1.2/AVRCP1.6/D11.3Compatible phoneCompatible with Android, iOS, Micr osoft, Symbian OS, 99% of Bluetooth phones and tabletsProduct SizeLength 2cm. Width 1.7cm. High 4.5cmProduct ListCharging box / i9 S headset / charging cable / manual / silicone protective cover (gifts) / boxDescription of use1. Listen to the song correctly, support the song and then call.2. For the iPhone power monitor, you can watch the power of the headset at any time, don't worry about the headset being powerless, you can worry about your life;3. One or two connections, you can connect two mobile phones;4. The Bluetooth headset is connected to the mobile phone after each shutdown, and then the Bluetooth headset is automatically connected back to the mobile phone, which is also convenient.5. A2DP / AVRCP high quality stereo audio transmission and remote control protocol6. Powerful noise denoising circuit (active noise reduction)7 Charging time is about 1 hour (power indicator charging: red light, full power: red light off (blue light).)   product upgradeThe price of the upgraded version is the same. When the headset is turned on, if you are an iPhone, then your iPhone will pop up a window like the picture below, prompting you to link the headset! a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a