Broan/Nutone 412H Round Transition Duct for Range Hoods and Bath Ventilation Fans - 7 3-1/4" x 10" to 7" round transition made to fit fan and hood outlets that must fit to 7" round ducting Transition is made of 30 gauge galvanized steel construction for durability and long life For range hoods and bath ventilation fans PLEASE NOTE: Item is not offset - it is centered. Picture appears to show it being offset but it is not.