At Amazon, I've seen
RN14 1/4"-20 steel rivet nuts,
RN516 5/16"-18 steel rivet nuts,
RN1024 #10-24 steel rivet nuts,
I also saw the following image explaining the size of a 1/4" rivnut, but it doesn't make sense to me.
So my question is: how wide and how long is an 1/4"-20 rivnut and what drill bit do I need to make the hole so it fits correctly? And what size eyebolt would fit this rivnut?
I'm buying the rivnuts and the eyebolts online, so I would need to be sure of the sizes.