This is a B & O railroad locomotive herald that used to mount on the front of B & O locomotives. I only ever saw one before and that one was cast bronze and was from a President class steam locomotive. I have seen them on the front of diesel locomotives and I know they were Alumminum. This one came from a deceased Railroad employee who had a large collection of B & O and Chessie stuff. I bought alot of his lanterns and cans, this was among the collection. It is mint condition and is 15-1/2 inches in diameter and weighs 5 pounds. It has three mounting screw theads holes and are all fine. It is 3/4 inch thick cast alumminum. I asked a local B & O collector about this herald yesterday and he believes it is a switcher locomotive [probably an SW-1 deisel] herald of the the 1940s. Reproductions of this item are usually made of resin and plastics and he advised me that this one is way underpriced. Oh well.