A reader wondered in a comment to the post on the Bessey boxcar what are the couplers on that car? Below is a close up.

It is what I would call semi-automatic coupler of some sort. Looking through my list of parts I have seen advertised I am hesitant to say what it is exactly based on that. There may be a magazine advertisement with a photo that pins things down further.

The coupler has a die cast body with the main knuckle being cast. The portion to the right of the knuckle as visible in the photo is spring brass. In other words, if two of these were pushed together just right they would couple but not by the type of action we think of with a modern Kadee coupler; the knuckle is fixed and the other side opens up a bit to allow the couplers to mate.

There is a brass rod that goes out to in the photo to the left. It is attached to the base of the coupler. If this is currently in the original factory position or not I am not sure but it must have had something to do with a system for uncoupling.

If any of you have examples of this coupler packed up as originally shipped and/or can identify this positively do let me know. It is an interesting design that will actually mate manually with standard OO dummy couplers as well which is part of what drove this design to market at the time.

UPDATE: My inclination for those wondering is to guess this is a K&W coupler. In the February, 1940 issue of Model Railroader (p. 110) it was reported that the K&W coupler was named standard by the NMRA for O, OO, and HO gauges. There is a good photo of their new O gauge version in that same issue (p. 107) but I have yet to find a good photo (or packaged example) of the OO version. Whatever it is on the car in the photo, it is a factory item, not something made by a modeler in my opinion.

UPDATE II: As this article seems to come up on searches, I have also added this early advertisement, reproduced from the June, 1939 issue of The Model Railroader. The models in the advertisement look to be HO models. I like that line in caps, “Send a dollar and be convinced.”