Comfortable and Heat Retaining Material: These heated socks are made of 80% cotton, 17% polyester and 3% spandex. They provide good insulation, remove excess moisture and create a comfortable temperature balance, so your feet will always be dry and warm on cold days.Far Infrared Function: The heating elements cover your toes and the soles of your feet. It uses far infrared heating elements to promote blood circulation, boost your immunity, and keep your feet warm in cold weather. We will test all of our products before delivery, so no need to worry about quality and safety.Three Temperature Settings: Our heated socks include two rechargeable 3.7V / 2200mAh batteries. When the battery is fully charged, you can use more than 7 hours. 3 temperature settings for your choice: high setting (red light 131/55), medium setting (blue light 113/45), low setting (green light 104/40).Suitable for outdoor activities. 'winter: The thick but light heated socks are perfect for many winter sports and activities such as skating, skiing, snowmobiling, climbing, hiking, fishing and traditional winter games. Perfect gift for your family, friends and the elderly during the cold season.Easy care: Hand wash and machine wash are both acceptable. When machine washing, it is recommended to wash heated socks in a laundry bag. Note: Please make sure to remove the batteries before washing them. Do not wring these socks. Do not iron.