A sliding arm door closer is a type of door closer that is used to open and close doors. It consists of a sliding arm that is attached to the door and a fixed attachment to the frame or wall. When the door is opened, the arm slides out and stays in that position until the door is closed again. Sliding arm door closers are often made of steel or aluminum and are designed to be strong and durable. They are often used on doors that need to be opened automatically, such as in shopping malls or airports, to prevent people from having to open the door manually. Sliding arm door closers are also suitable for use on heavy doors or doors with a large surface area, as they are able to support the weight of the door while ensuring a smooth movement.