Wondering what this contraption on the roof of a neighbor’s house is, I showed this photo to GPT5 and here is what it said:
This is a chimney cowl — a device placed on top of a chimney to improve airflow and prevent downdrafts.
The specific type in your photo is a rotating, directional chimney cowl, sometimes called a “H-shaped” or “dragon” style cowl. The curious shape with the curved metal and the little vertical stub helps the wind create suction, drawing smoke up and out instead of letting it blow back into the house.
Besides preventing downdrafts, it also helps keep rain, birds, and debris from getting into the chimney.
This one seems to be an older, somewhat weathered model with a quirky design, which makes it look almost like a piece of abstract sculpture!
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