355mm Flexible connection, used to fit to Flanges (with spigots), Silencers (with spigots) or spiral ducting.
A flexible connection is used to isolate the fan from the system to prevent vibration transfer and helps minimise noise transfer through fixings or structures.
It can also be used to simplify installation by bridging any small gaps between sections of the installation, for example the gap between a fan and the ductwork