Plastic 6-Inch to 5-Inch, 4-Inch Converter Cone Reducer for flexible/PVC Pipe | eBay
Amazon.com: DuraVent 3PVL-X6 PelletVent Double-Wall Air-Insulated Pellet Stove Chimney Adapter with Stainless Steel Inner Wall and Galvalume Outer Wall, 6" Diameter : Home & Kitchen
AllFuelHST Stove Adapter for 6" Single Wall Stove Pipe - ComfortBilt
Imperial Black Stove Pipe Reducer, 24-Ga., 6 x 4-In. | Central Hardware & Furniture
Chimney Liner Accessories & Supplies: Adaptors, Boots & More
6 Inch to 4 Inch HVAC Duct Reducer & Increaser - Galvanized Sheet Metal Ducting Connector for Airflow, Heating, Cooling, & Air Ventilation System Extra Strength and Fittings - Ducting Components - Amazon.com
6 Inch to 4 Inch HVAC Duct Reducer & Increaser - Galvanized Sheet Metal Ducting Connector for Airflow, Heating, Cooling, & Air Ventilation System Extra Strength and Fittings - Ducting Components - Amazon.com
8 to 6 Plug Reducer 22GA Black - 21551 - Increasers Reducers & Adapters - Single & Double-wall
4 to 6 stove pipe reducer
Harvia Adapter Pipe WZ115155 4" to 6"
IMPERIAL 6-in x 8-in Black Steel Stove Pipe Increaser in the Stove Pipe Fittings department at Lowes.com
Cox Hardware and Lumber - Galvanized Stove Pipe Reducer, 7 In x 6 In
Riley Stove Stove Pipe Reducer 4 inch - Riley Stove
Imperial Manufacturing GV0811 Short Duct Reducer 30 GA Gauge Galvanized Steel: Stove Pipe Galvanized Increaser & Reducers (063467110965-1)