Naiture 2-1/4" x 10" Solid Brass Floor Register Mission Style Brushed Nickel Finish Duct opening size: 2-1/4" x 10"(3-1/4" x 11-1/4" Overall) Made of heavy-duty solid cast brass for durability. Finished with a durable brushed nickel powder coat finish to resist rust. Louver control extends 3/8" H from vent which could control air flow easily by foot. To determine size needed, measure air duct opening rather than old register or grille.