... for 7-8 hrs Hot cute reusable electric hand warmer details:Specification: Size:L85*W62*H20mm Weight:70 ... .for low temperature, .for high temperature.When the warmer is ON, then the LED indicator turns red, at ... a dry place.During use and storage, if the warmer appear abnormal phenomena such as smelly, hot, discoloration ... and so on. USB Rechargeable battery operated hand warmer with 1800mAh power charger