Product Features: Item Number: M6 PLUS Bluetooth Version: Bluetooth V5.0 Battery Specification: Headset 3.7 V / 40 mAh; Charging box 3.7 V / 300 mAh Support Mode: HFP / HSP / A2DP / AVRCP Sensitivity: 105 dB ± 3 dB SPL at 1 kHz Transmission distance: 10 meters (in perfect environment without any major obstacles) Working time: about 2.5 hours Call time: about 3 hours Standby time: about 100 hours Charging time: charge the charging compartment for about 2 hours and charge the headset for about 40 minutes Headset charger: about 2.5 times Temperature measurement 1. The case is sufficiently charged in the charging box, contact the sensitive part of the body temperature measurement with a temperature sensor. 2. Press the charge button 3. After 5 seconds, the LCD display of the charging storage will enter the temperature measurement display. The whole process of measuring temperature will take from 8 seconds to 10 seconds. 4. After the temperature control is stabilized, the LCD will display the human temperature 5. Press the charger to switch between Fahrenheit and Celsius.