The warm, comfortable and healthy integrated heating element covers the entire front foot. Heat quickly, and you can feel the temperature in 20 seconds. Enjoy a warm winter for people with Raynaud's disease, arthritis, poor blood circulation, stiff joints and cold feet for a long time. 3-stage adjustable temperature The 3-stage thermal regulator setting allows you to adjust your preferred temperature. Heat at 45 C/113 F for 10 hours (one light is on), at 50 C/122 F for 8 hours (two lights are on), and at 55 C/131 F for 6 hours (three lights are on). Heat for 6-10 hours, and charge the battery for about 3 hours. Soft and breathable materials have the characteristics of breathability, water absorption, quick drying, thickening and elasticity, and are ideal for outdoor activities in winter. These winter socks are equipped with 3.7V 2200mAh lithium ion rechargeable batteries, which have a long service life. It is widely used for various indoor and outdoor activities, such as hunting, hiking, horse riding, fishing, cycling, driving, running, camping, skiing, mountain climbing, walking, sleeping, etc. Friends, family, year, etc. One size fits all, easy to clean. One size fits all men and women. Long tube cotton socks can cover the calf, and can be widely matched. There are two ways to wash warm and fashionable socks. Hand wash after taking out the battery; You can also machine wash it. Note: A laundry bag must be added to protect the thread.