The depth of just the frame is 1 1/4 but the 3 dimensional decorative grille areas bows out. The top handle when pushed opens the damper portion open about 3.The inner portion of the vent is 9 3/4" wide x 7 7/8" long. There are no maker's markings on the piece other than the inner steel open/close panel reads: Ko on one side and the number 1 on the opposite. This frame is solid cast iron weighing about 5 1/2 pounds. The item "Vtg Cast Iron Grate Register Diffuser Grille Metal Farm Architectural Vent Cover" is in sale since Saturday, October 26, 2019. This item is in the category "Antiques\Architectural & Garden\Hardware\Heating Grates & Vents". The seller is "cherylgeek" and is located in Racine, Wisconsin. This item can be shipped worldwide.