3 Heating Settings to Keep Your Feet Warm: Heating socks have three temperature Settings that you can choose according to your preference to keep your feet snug and warm. ⁰ (40⁰C/104⁰F), medium (50⁰C/122⁰F) or high (60⁰C/140⁰F). No matter how cold it gets, you can rely on these heated boot socks to keep your toes snug. Durable upgrade batteries: Battery-heated socks last 4 hours on the highest setting and 9 hours on the lowest setting, so you don't have to worry about running out of power quickly. With constant charging, you can even enjoy using electric heating socks for long periods of time without any problems. You're free to go on long walks or trips, and these electric warmers keep your feet comfortable. Charge your battery heating socks at the same time: These two updated versions of the rechargeable electric heating socks can be charged simultaneously via a specially designed wire. The cable only needs to be plugged into a USB port, so you don't have to worry about spending money on extra adapters or power banks. With a charging time of just four hours, your USB charging sock can warm you up in no time. Great for winter sports and outdoor activities: Cold feet can often take the fun out of any outdoor activity. With these electric socks, you can hunt, camp, ski, or snowboard without freezing Anyone who loves the outdoors or lives in winter can use these electric hunting socks in the cold. Soothe your feet with soft, high-quality materials: Enjoy materials that keep your feet warm and comfortable without having to worry about itchy or bulky batteries. These electric thermal socks are made of specially designed cotton fabric that feels soft and breathable, while the spandex fabric perfectly supports the arches, ankles and toes. The batteries on these charging socks are easy to remove and inconspicuous, so you don't have to deal with the extra weight.