The Helios Fans ZAV 125 is a polymer air valve designed for flexible use in ventilation systems. It supports both wall and ceiling installation, making it adaptable to various setups. When installed on walls, the valve functions with an adjustable front grille, while for ceiling applications it uses a closed front grille combined with an open aperture ring. The ZAV 125 is suitable for both intake and extract air applications, providing efficient airflow control in residential and commercial environments.