This is a really well-made, shiny, nice-looking, mail slot cover. As far as I can tell, it’s solid brass; it feels heavy and solid (compared to my old brass-plated cover) and a magnet won’t stick to it. It comes in a nice box with eight screws, which I guess are brass, too, and a matching frame-style brass plate (minus the center flap) for the inside of the door. There were no instructions in the box; I ended up making my own template to position the screws.It was put on the carved-out mail slot of a thick wooden door on a 1950s era house. The only thing about it is that the carve-out must be sufficiently large to accommodate the raising of the flap on the cover, because the top of the flap raises into the top of the carve-out. Like a swing-up garage door. Hope that makes sense.I initially bought the cover to cover the interior side of the mail slot to reduce drafts and bugs; however, the flap of the cover wouldn’t open properly without positioning the cover such that there would be a gap at the top. The carve-out on the door is curved at the corners and prevented the flap from flipping up.I don’t have the tools/capability to carve out more wood. Instead, I tried it on the exterior side of the door. I took off the old exterior brass-plated cover and found that this new cover would fit on the exterior of the door. The old cover, fortunately, easily fit the interior side. So, win-win. The better looking cover is on the exterior and the old cover is on the interior.One thing I really like about it is that it solidly and tightly springs closed with a little bang. There’s almost no draft, though there are two small air gaps in the upper left and right corners of the cover; and I doubt a roach could get through. In this respect, it worked out better that it’s on the exterior of the door.As I mentioned in the first paragraph, it does come with a matching, rectangular, frame-style, brass plate meant for the interior side of the door, but it has no flap so the center is wide-open. I like my door better with both sides having flapped covers.There have been no problems with mail delivery in having both sides fully-covered. In my case, the flap of the interior cover is really loose making it easy for mail/magazines to slide through.