This new 6-inch to 4-inch flexible air duct reducer adapter is a practical choice for connecting different duct sizes in ventilation or air ducting setups. The listing identifies it as a silver air duct adapter/reducer, making it relevant for buyers replacing an existing fitting or adapting a vent line to a smaller diameter. Free shipping is included, which may help reduce overall project cost. Because the title includes both flexible ducting and reducer adapter terms, it may suit shoppers looking for a basic HVAC or vent connection part. Size is an important buying note here, so confirm that 6-inch to 4-inch sizing matches your system before ordering. Check the listing for full details. Air Ducting vent Flexible Duct Reducter 6" to 4" Air Duct Adapter Sliver. Color: Silver, Condition: New. Listed at 13.99 USD. 【Size】 Made of galvanized steel. Round Ducting Adaptor. 【Easy to Install】 Put it in the two ducting, easy to install the air duct reducer.