I bought five of these about 35 years ago, but never had a chance to use them, so I stored them in a warehouse. There are some areas with dirt and rust. They are lovely iron electric lamp shades. I had a professional install one of them. The base is square, with one side measuring approximately 35cm, the top side is approximately 13.5cm, and the height is approximately 25cm. The last photo shows the one I have installed; I believe it has the spare chain attached. The other four don't have chains that are as long. They have been stored in the warehouse as they are, and I haven't checked their functionality. I think you'll need to have a professional install them. I have checked them, but there may be oversights. Please refer to the photos and consider purchasing. No returns accepted.