Our filter is easy to install, no, thermal bonding;. 1 set of conical exhaust valve filter. Function: for Zehnder, for for Helios, for Maico, for Pluggit Ventilation Valves - For Exhaust Valve/Butterfly Valve Ventilation Units, Cone for Bathroom or Guest Toilet Ventilation s, Cone Synthetic Without Adhesives Fleece standard size, easy to install.
