- The clever way 2-pack G4 / F7 filter for your ventilation unit For clean, allergen-friendly indoor air Replacement for your current air filters Tool-free filter replacement All compatibility and technical details below Keep your ventilation unit running efficiently with these replacement filters. The G4 pre-filter captures large particles such as hair, insects, sand, and coarse dust from the incoming air. The F7 pollen filter provides additional protection by capturing fine dust and pollen. These filters prevent outdoor pollen and dust particles from entering your ventilation system. Filters are easy to install without tools into the designated slots of your ventilation unit. To maintain optimal performance, replace the filters regularly. This filter set allows you to upgrade your ventilation unit to F7 pollen filter class without needing an external filter housing. NOTE: Airflow direction is marked on the filter media. Package includes: 2 x Filters (G4 / F7) Technical specifications: Dimensions per filter (L x W x H): approx. 50 x 17 x 1 cm Filter class: F7 (red pollen filter) / G4 (black pre-filter) Type: Pollen filter / Pre-filter Material: Synthetic fiber / Plastic Color: Black / White / Red Compatible with the following models (use Ctrl + F or Cmd + F to search for your model): Zehnder ComfoAir 350, 550, 300 Standard, 375 Standard, Zehnder ComfoD 300, 350, 450, 550, Paul Santos 370, 570, Wernig G90-380, G90-500, G90-550, Wernig ComfoAir 350, 550, Aeris 350, 450, 550, R+F ComfoAir 450, R+F Optiline KWL 350, Sanibel ComfoAir 350