An Air Curtain Machine, also known as an air door, is a device that creates an invisible barrier of air to separate two spaces. It works by blowing a stream of high-velocity air across an opening, such as a door or window, to prevent outside air from entering a building or inside air from escaping. This can help to maintain a comfortable temperature and reduce energy costs by reducing the need for heating or cooling. Air curtains can also help to keep out insects and dust, making them a useful addition to commercial and industrial buildings. They come in a variety of sizes and can be installed in both new and existing buildings. They can be powered by electricity or compressed air.