Rotary vents, also known as circular vents, are ventilation devices used to regulate the flow of air in HVAC systems. They are typically circular in shape and consist of multiple blades that rotate around a central axis to adjust the direction and volume of airflow. Rotary vents are commonly used in residential and commercial HVAC systems to control the flow of air into different areas of a building. They are often installed in walls, ceilings, or floors and can be adjusted manually or automatically to direct air in a particular direction.The blades of rotary vents can be made from a variety of materials, including plastic, aluminum, and steel. They are usually adjustable and can be angled to direct air in different directions, making them useful for directing air towards specific areas or away from obstructions.