An insulated thermos is a container designed to keep liquids hot or cold for extended periods. It typically features a double-walled construction with a vacuum seal between the walls, which minimizes heat transfer. This design helps maintain the temperature of beverages like coffee, tea, or soup, making it ideal for travel, outdoor activities, or daily use. Many insulated thermoses are made from stainless steel, which is durable and resistant to rust. They often come with a secure lid to prevent spills and may include additional features like a built-in cup or a handle for easy carrying. Popular brands include Thermos and Contigo.