Function: High strength composite material, can radiate infrared ray, promote blood circulation. Battery pocket design, with 2 dry battery boxes, for portable use. Easy to use, high heating and high thermal insulation. The heating temperature is about 50 constant temperature, more convenient. Comfortable to wear and protects your feet from the cold, for both men and women. Specification: Item Type: Electric Heated Socks Material: cotton Battery Voltage: 4,5 V Battery Life: Disposable Size: Foot length: about 21 cm/8.3 inch Pipe length: about 27 cm/10.6 inch Using the new brand of dry alkaline battery, you can continue working for about 4-5 hours. Use: Before using this product, you must first purchase 6 dry 1,5V AA batteries (it is recommended to use dry alkaline batteries), and each battery box contains three dry batteries. Once the battery is installed, insert the DC head of the heating socks into the DC port of the battery box and move the switch on the battery box to the ON position. During this time, the red LED on the battery container lights up, the socks start to heat up, and the heating temperature is about 50 . If you feel overheated or want to stay warm, set the switch on the battery container to the OFF position to close, that is, turn off the power. It can be kept warm for a while. The heating temperature changes with the ambient temperature. List of packages: 1 pair of electrically heated socks 2 x Dry Battery Container 1 x User Manual Note: Do not allow children to have access to batteries. If you feel discomfort, immediately remove the electric socks and consult a doctor. Children and pregnant women should not use them until they have consulted a doctor. Stop using the product immediately after contact with water and do not use it until it dries. Heating. The following apply only to 4,5V electric socks: The LED of the battery box is turned off because the battery is weak. Please stop using it immediately and replace the battery. If you do not use the product for a long time, store the product in a cool and dry place. It is strictly forbidden to put the used battery into moisture, water, fire and high temperature.