They are mainly used for chimney flue liners and ventilation ducting system. Chimney Flue Liner Reducer.
Galvanised Steel Reducer Duct Pipe Metal Connector Adaptor Chimney Flue Liner
Reducer Ducting Pipe Connector Adaptor Chimney Flue Liner Stainless Steel
Chimney Flue Liner Metal Reducer Ducting Stainless Steel Pipe Connector Adapter
