What are these flatbeds used for?

Dumb question from a door swinger but here goes.. I can't find a picture to show you what I'm talking about, but every now and again, I see deadhead flat with maybe 8-10 tall vertical poles mounted in a straight line down the center of the deck. No A-frame or anything just the pipes. So what is the purpose of these? I imagine that the trailer is dedicated to one type of freight but can't figure out what.

 

I tried that. Apparently Fox Sports Radio wasn't sexy enough cuz I didn't see any girlies.

 

Nope. These steel pipes are in a straight line, dead center of the deck running front to back. They are usually pretty bent up and on some beat up trailers. No spreads just tandems or at least the ones I've seen. Not like that helps but it's all I really know. I'm still looking for a picture to help