Originally Posted by Gordon in Idaho
I'm sorry I didn't explain it better, but we're talking about different kinds of expansion nuts. These are the type that I have used:
These are available at larger hardware stores, and don't require a special tool. However,they DO require the courage to drill some 1/2" holes in your trailer!
Anyway, just wanted to clear that up.
OK, now I'm seeing the drawing a little closer. Yes, I was thinking of Riv-Nuts because I was just looking at the machine screw being inserted in it. When I looked at the pictures you posted a little closer, I see that they are indeed well-nuts, (aka neoprene expansion nuts.)
Just need to wear my reading glasses more often.