What is this Called and Where do I Buy One?

T Slot nuts. I'll check on it. Thank you!

The picture is a T slot nut but the description is something else. If it crimps into a sheet metal panel the protrusion would be much less. If this was factory fitted it might not be available as a spare & could be difficult to install. As Spades suggests, a cage nut with the right thread could work well.

Thanks for the info. You're correct about the T Slot nut being different than what I'm looking for. When I wrote that it crimps on, what happens is that the nut is placed into the sheet metal and the nut face (A in the diagram) is distorted to hold it in place (what I called crimping).

Using a cage nut may be something I do, but first I'm going to try a plastic one.

Thanks for the info! I like the plastic nut idea, since it should hold well and if I need to enlarge the hole, it'll be easy to do. The cage nut also seems like a good idea, so if the plastic nut doesn't work, I'll try it.

If this is steel you might be able to tack weld a nut in place...I had this problem on aluminum, and ended up gluing it in place...I would check the enthusiast websites for any info, and ebay...and youtube...

...you also might consider some type of clip on nut....

https://en.wikipedia.org/wiki/Cage_nut

Thanks Solar!

I'm not a welder, so that wouldn't work - it's something that I've always wanted to learn how to do!

I'm probably going to use the plastic snap in piece. So, in the future, if someone wants to bring the car back to factory specs, they can (in case it ever becomes a true collectible).

You're good! That's my door panel (different color, but same panel)

^{Is it one of these?}

Thanks for the tip! I'm going to try one of these plastic nuts first. If it doesn't work, I'll try the cage nut.

A more general term is "press nut"; they come in many configurations, typically from industrial fastener sources. "PEM" is one brand name.

Press nut. Thank you. I'll see if I can get one.

Found this, called rivet nut....

25pcs Silver Flat Head Rivet Nut M8 for Automotive Insert Nutsert

...cheap $4.

...but you need the threaded insert tool....cheapest one $22 harbor freight

https://www.harborfreight.com/45-piece-threaded-insert-riveter-kit-1210.html

Larger individual sizes....

https://www.grainger.com/product/33JE76?cm_mmc=PPC:+Google+PLA&s_kwcid=AL!2966!3!50916712317!!!g!82128166197!&ef_id=WB38gQAABcDVdELg:20180828004957:s

Maybe you could just fiberglass the hole and use an insert....or pc7...

I've seen these. I need something square. Thanks for the info.

That's it! Pierce nut.

I was thinking of crimping it in with a portable mini vice and putting some chunk of hard metal between the vice and the nut. That way, the hard metal will deform the nut and hold it in place.

Or I can glue it in too.

That's where I found one of them. One was still in the door frame and one had fallen into the inside of the door. The other is lost.

I'm just a bit perplexed: why didn't you take a picture of the one that came out, and show us the actual dimensions?

I'm not looking for someone to lead me to an exact part. I can find one, but I didn't know what it's called, so I had nowhere to start ... well, I actually started on Amazon and found the one with a slot (the picture on my original post). It's not the right one of course, but I knew someone here would be able to lead me to the right place.

Pierce nut - that's what I need to get.

Giving dims. would help considerably.