Bolts for OEM skid plate?

I had bought a OEM skid plate on another forum. I was wondering if anyone knew the bolt size for the skid plate. The skid plate looks like this


What size bolt do I need?

 

What size socket fits them? I forget. 17mm or 14mm socket? I think they're 12mm x 1.25. That's a guess w/o having one in my hand, so I'd wait for more feedback.

 

I recently had to replace mine due to them being stripped out, I got some from O'reilly and they take a 13mm socket, i don't know exactly what thread they are but on the head of the bolt it says J D 10.9 hope that helps some! Also, is that all that you got for the skid plate? I think there should be another part that extends farther back, at least that's what is on my truck. This isn't mine, but it looks something like this:

 

Thanks for the reply! I got everything taken care of, thanks!