Original WSF 320/470 replacement air filter item no. 0092.0559 from Maico fans, packaging unit 1 x F7, for central ventilation units WR 310, WR 410, WS320 and WS 470 : Amazon.de: DIY & Tools
Wolf CWL 300/400 Excellent | G4+F7 | With a discount up to 20%! - KWL-FilterOnline
vhbw Filter Set Compatible with Paul Santos 370, 570 Ventilation Unit - Air Filter G4 / F7 (Pack of 2), 50 x 17 x 1 cm, White/Red/Black : Amazon.de: Home & Kitchen
Maico WRG 400 EC - Filter set G4 + F7
vhbw Filter Set compatible with Zehnder ComfoAir 180 Ventilation Devices - Air Filter G4 / F7 (2-Part Kit), 24 x 12 x 5 cm, White : Amazon.co.uk: Home & Kitchen