Grid Design Heat Grate, Oil Rubbed Bronze. 4" x 12 inner dimensions, 6" X 14" outer dimensions. Cast of solid aluminum with a hidden lip that fits into your duct. A full 3/16" thick, most sizes are suitable for either floor or wall mounting and come with or without attaching holes and screws. Louvres sold separately. Finished with a beautiful baked-on powder coat finish. Thickness up to 1/4". Smooth finish with no sharp edges. These products are of the highest quality on the market in regards to casting quality and durability. Quality guaranteed.