Question about PTC Trains

I've recently noticed something on PTC trains. I like to put my feet up under the seat in front of me and have noticed that there is what feels like a steel rod stretching across just under the forward seat. It's a few inches off the floor board and I usually rest my feet on it. Does anyone know what this steel rod does? Is it something that mechanically works with the lap bar locking mechanism or something to stabilize the train body? Any ideas?
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Nashville needs a theme park!

I think that's a metal plate that holds the top of the car frame together. If I remember correctly, the seat back is just sort of pinched in between the rails on the seat sides, so the seat back doesn't provide any gauging strength. In fact, I think that's why a lot of PTC cars have a length of wire rope stretched across the back of the seat back...to hold the upper part of the seat together.

Anyway, the plate runs the full width of the car and holds the side rails together.

--Dave Althoff, Jr.