What is this at the front of the bed of my truck?

This is probably going to be considered an idiotic post, but I have gone through the entire manual and really have no clue what to search for to find out if someone else already posted.

I'm talking about the bar with the little metal piece that sticks out at the front of the bed of the truck (I'm interested, because I'm trying to figure out what to do to mount my hi-lift jack, and so far all of the options I have found I don't like. Closest is RCI, but it doesn't seem locking.):

 

My truck just has the mount holes for that plastic doo dad..

What is that?

 

Your truck had a Tonneau cover, it was the support for it.

Don’t feel bad- three Toyota trucks and I asked what the square hole was above my rear license plate - tells something about all those BFG’s I owned over all those years!

 

"Has" one... yeah... sitting in my garage... this seems to be the answer! Thanks.

 

It's for the factory cover. Used to align the it in the bed if you take it off and put it back on.

You will still be able to install a 3rd rail under it with no interference

 

. I know you read it, couldn’t resist

 

It’s so toyota can still use the same bed from the 2nd gen but raise the bed rails. They also use it to attach the tonnoeu cover.