The car you describe is a NP RBL. If a 50’ car first put into service 1957. If a 40’ car first put into service 1958.
There were many variations to these cars – rivet, welded sides; diagonal panel, PS roof; sliding flush doors; several loading systems as shown on door. Any further spotting features especially car number would allow more precise dating.
From: email@example.com [STMFC]
Sent: Sunday, August 28, 2016 2:39 PM
Subject: [STMFC] NP Plug Door Box Car
I have a photo showing a green NP box car with yellow(?) stripe and what appears to be a "DF" circle logo on its plug door. Northern Pacific is in arched lettering to the left of the door and there is some lettering to the right of the door, perhaps for the North Coast Limited, along with the NP trademark. Could someone tell me when these cars would have first been put into service. I am trying to date the photo and this is the most distinctive car in the train.
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