1. Warm Fleece Lining: Our heated ear muffs have soft, cozy Polar fleece lining that provides additional warmth and comfort, effectively shielding your ears from icy winds and low temperatures. Equipped with an automatic shutoff function (over 55° C) for and power conservation, preventing overheating and extending battery life. 2. One Size Fit Most: It has good stretch, suitable for a head circumference, which is suitable for most different head girths. Embedded with elastic memory wire, it ensures stable wear and will not fall off. 3. Widely Used: Suitable for both men and women, these heated earmuffs are a fashionable accessory for various outdoor activities such as hiking, skiing, running, or simply for everyday winter wear. They are the perfect gift for family, elders, colleagues and classmates during festivals like Christmas, Halloween, Thanksgiving, Easter, as well as on birthdays, at parties and anniversaries. 4. Fast Heating and Adjustable Heating Levels: The heated earmuffs are builtin with a PI heating pad, achieving three seconds quick heat. You can choose from 3 heating levels (Low: 45° C Medium: 50 ° C High: 55° C) to suit your comfort preferences on cold days, ensuring your ears stay comfortably warm without overheating.