Feature:

-2200mAh battery usage time & Temperature indication: Low heat (45), can be used for up to 10 hours. Medium heat (55), can be used for up to 7 hours. High heat (65), can be used for up to 5 hours.---4000mAh battery usage time & Temperature indication: Low heat (45), can be used for up to 20 hours. Medium heat (55), can be used for up to 16 hours. High heat (65), can be used for up to 11 hours. Battery charging time: Approximately 4 hours

-How to use: Start charging the included 3.7V batteries. Connect the batteries to the cables in the pocket on top of the sock. Turn on and hold the power button on the battery for 2 seconds

-Washing instructions: 1. Make sure to remove the battery Compatible with washing and insert the battery cable into the battery pocket (note that the battery cannot be washed)

-Battery maintenance: 1. It should not be soaked, dropped, or disassembled. 2. The battery should be Compatible with stored in a dry and cool place.