The Frost King V73/3 Window Insulation Shrink Kit is designed for indoor use to help insulate windows and save energy. This 3 pack includes clear window film sheets that measure 42 inches by 62 inches each. The film is intended to be applied to windows and then shrunk with a hair dryer to provide a tight seal and improve the window's insulation properties. Perfect for keeping out drafts and reducing heat loss during colder months, this kit is a practical and cost-effective solution for improving the energy efficiency of your home.