I had to look through my supply box to find one so I could tell what a 2542 is. No longer pictured on the Atlas site. I have a couple boxes of these that I must have gotten many years ago with some other stuff. Never used any and, like you, I'm not sure how I would use them. Charlie
I don't even know what a 2542 looks like. Maybe if you post a picture of the thing people might recognize it.
It is a straight bridge girder (not a girder bridge). Just a piece of plastic to support the track between piers. It doesn't really have an equal in real life so I doubt many people other than those building their first layout use them. A bridge is a much better choice to replace them.
¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤ has them: http://www.¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤.com/product-p/atl-2542.htm The picture shows it up on edge, as though you were looking down on it from above: Hmm... that's interesting... some sort of auto-business-name-deleter. Umm... this prominent retail MRR outlet carries them, and you can see a picture on their site.... Umm... WTH? Did we have to get even stricter than we already were about posting links to retail spots? This isn't even an editorial comment, just an attempt to link to a product photo and provide objective information relevant to the OP. Oh well. This other popular retail site and Trainboard advertiser also carries them. And THIS link appears to work! Edge on, it's not much thicker than the track itself.
They made those in HO too. When I had hair. The only use I ever found for them was that mounted UNDER the regular 'girder and truss bridges' they made them look a lot less ridiculous from the side. Even a through girder bridge has to have something under the rails. Ties don't cut it.
These were sold to support the track on a figure eight up and over layout. It was meant to prevent sagging. As said, not a prototypical structure.
I think I have some of these. Never used them "as a bridge." What I keep them for is kitbashing fodder-- structural "stuff." I plan to build a vertical lift bridge one of these days for the 2-lane auto causeway alongside the Scherzer rolling lift bridge on my rail causeway, and I may find a use for some of these. I plan to use two of the little Atlas 5 inch through-pony-truss steel bridges STANDING ON END as part of the end support towers for the vertical lift bridge. One of these days...
Here's an explanation: I control the software. There's your explanation. - Kida, sorta, really weird Charlie
Oh, OK, no doubt there. Didn't figure out a filter at that level, sorry. As carpenters say, it's FINI. At 11,327.