... battery keep warm for 7-8 hrs Hot cute reusable electric hand warmer details:Specification: Size:L85*W62 ... .for low temperature, .for high temperature.When the warmer is ON, then the LED indicator turns red, ... power, and then you can use the warmer again.Warm reminders: The battery is low, then ... dry place.During use and storage, if the warmer appear abnormal phenomena such as smelly, hot, discoloration ...