"Of course these aren't the rarest of horns, but back in Denver, Colorado two days ago I found these. Just a bit of an interesting setup."
(comment)
AA: "Heated back cap model with electrical earth straps. Those back caps are also used as under loco low note horns but with no threads tapped in the center lug for hot air heating of diaphragms The horn points downwards at the track and water can be repelled off the back cap and not into the back cap holes as per standard Nathan cap covers as it has one small vent hole in its side. They are used in Australia."
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