Product Advantages: ❄NO MORE COLD FEET IN WINTER---Heated Electric Warm Thermal Socks,Battery Operated Winter Foot Warmers For Men&Women, Warming Socks Get Toes Warm In Cold Weather Indoors Outdoors Sports Heating Socks - Colors May Vary. ❄UNIQUE DESIGN PERFECT FOR MEN&WOMEN,BOYS&GIRLS.This size is M,as investigated,the size fit most of people as this new invention thermal socks has great elastic. ❄PORTABEL&FOLDABLE/EASY TO USE/EASY TO CLEAN. 3 heated settings for varies needs,Cozy&Warm enough but not hot for different people’s needs.Keep your feet Warm all day long in winter. ❄LONG WORKING HOURS+TEMPERATURE ADJUSTABLE.Each battery has 3 heat settings-Red/orange/green.Red light is the highest setting can last 3-3.5 Hours,Orange light is the Medium setting can last 4.5-5 hours,Green light is the lowest setting can last 6-6.5 hours.In order to save more battery life,You can set the socks at temperature-High(Red)at first,then you can change to set it at setting-Low(Green).You wil feel fine. ❄ONE MUST HAVE WINTER NEW INVENTION SOCKS FOR UNBEARABLE WEATHER.Great fit for all kinds of indoor outdoor activities.Electric battery operated heating socks are fashionable practical and special design for cold weather. Please note:The 3.7V batteries is not full or it is out of power,it need to charge the battery full before use. Special Notice: Hand Wash,Soft Wash. The 3.7V Batteries May Not Come Full or It is Out of Power,It Need to Be Fully Cahrged Before Using. It Need to Charge the Batteries about 12 Hours to activate for the first time,Then 5 Hours Each Time. Please Charged the both batteries at the same Time.If the batteies are fully charged,the charger light turns red to green,not the battery light.