Originally Posted by the old geezer
the lock bars are used as a mechanical stay between the slide and the trailer body, placed inside near the top of the slide, and a bit like an acrow prop. I had one on my first trailer but never used one since. I don't think they are needed.
I disagree with you on your statement about them not being needed. I guess the emergency trailer brake release or chains are not needed either?
These bars serve two purposes. First they lock the slide so it can't move. God forbid you break a shear pin or cable when you bring the slide in. These bars pull the slide in tight against the trailer so it can't move. Second is it pulls the top in tight so you can't develop a water leal between the slide and trailer.
They can be used for other uses such as a bar in the shower to hang wet clothes on.
Here are two photos. If you have a sticker on the trailer wall, easily seen with slide out, then you should have the bars. Maybe under the couch?
NOTE: I didn't measure them but they are fully adjustable from about 2 feet to 4 feet long.