Made from stainless steel this adaptor plate resists acidic corrosion caused by condensation and rainwater which can sometimes get into the flue system. The Conical design of the plate means that there is no flat surface for soot to build up on as there would be on a conventional register plate. The long neck on the adaptor plate makes fitting your stove easier and creates a better seal. It is specifically designed to work with modern standardised 8 inch concrete flues.