Antique Cast Iron W Whistle Railroad Sign embossed vintage transportation For Sale

This is a vintage or antique \"W\" sign, which I\'m told was used in railroads as an indicator for the train conductor to blow the whistle as the train approaches a stop. It\'s all original cast iron with black and white paint. It measures roughly 16.25\" tall x 16\" wide, and the hole at the bottom is roughly 2.75\" in diameter. The hole at the bottom would have mounted on top of a post. There\'s a square bolt to tighten against the post to hold it in place. This is a rare one, and in good vintage original untouched condition.
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