The stainless steel non-return valve is an for those looking to improve their home's ventilation system. It is compatible with a variety of exhaust ducts and can be used in both residential and commercial settings. This valve not only prevents backflow but also helps to reduce energy consumption by maintaining a consistent airflow. Features - Color: Silver -Material:Stainless Steel - Size: 19.00X19.00X4.50cm/7.47X7.47X1.77in - Size: 15.00X15.00X4.50cm/5.89X5.89X1.77in -Extensive usability: suitable for dryers, extractors, range hoods, and other hvac systems, ensuring wideranging applicability -Valve: incorporates a check valve to effectively prevent backflow of smoke , keeping the environment clean -Simple installation: designed for easy installation, making it ideal for use in both kitchen and bathroom range hoods without help -Silent operation: engineered for quiet performance, ensuring no noise disturbance during operation, providing a peaceful home environment -Adjustable valve design: equipped with an adjustable valve to accommodate different airflow needs, offering flexibility and optimal list: 1pcs valve