WELLAND 4 Inch x 12 Inch Maple Hardwood Vent Floor Register Self Rimming Unfinished Fits a duct size opening of 4" x 12", Overall dimension is 13.6" x 5.6" x 0.75" Made of Unfinished Solid Grade A Maple Wood Self-rimming (drop-in) installation, louvered design Also known as insert vent Authentic WELLAND Product Made of three parts ,Easy to install Self-rimming (Drop-in) installation, louvered design insert vent Please read carefully Fits a duct size opening of 4&#034; x 12&#034; overall dimension is 13.6&#034; x 5.6&#034; x 0.75&#034; Measure the size of the duct opening. Do not measure your current floor register. Fits a duct size opening of: 4&#034; x 12&#034; Note:you must measure the size of the duct opening VARIETY- Red Oak, white oak, hickorymaple and so on Different size and different materials.