Swirl Replacement Filter Set, (G4 + F7) for Zehnder ComfoAir 350/500/550, ComfoD 350/450/550, ComfoBox, ComfoFond-L Eco, Paul SANTOS (F) 370 / 570DC (cool), Brine Defroster SD350 / 550 , Wernig G 90-380-500-550 / ComfoBox