General description The vhbw conical filter is designed for ventilation systems, specifically to prevent contamination in the exhaust air ducts while ensuring quiet operation of exhaust air valves. This filter is a high-quality replacement for the Zehnder 990320032. Technical specifications Filter class: G4 Filter size: DN 125 Diameter: 12.5 cm Length: 18 cm Width: 18 cm Thickness: 0.8 cm Material: synthetic fibre Colour: white Binder-free, thermally bonded Compatibility and accessories Fits all round exhaust air disc valves with a mounting ring diameter of 12.5 cm (DN 125) Installation Valves are secured into the mounting frame/mounting ring using a quarter turn Usage Designed for use in ventilation systems to maintain air quality and system efficiency