Pressure Louver PL – Efficient Airflow Control for Duct and Wall Installations. The Pressure Louver PL is designed for effective ventilation in both supply and exhaust systems. Manufactured with a durable anodized aluminium frame and blades, and a galvanized steel duct version, it ensures long-lasting performance in demanding environments. Ideal for duct or wall mounting, this louver provides optimal airflow with minimal pressure loss. Options include overpressure or underpressure configurations, duct-type design, and installation subframe.