Underbody protection or rocker rails??

[H3 Hummer]

I have both and put them on mysyelf the first month I owned the truck. Allthough the undercarriage is just as important in my opinion it does have something down there. So you are not totaly uncovered unlike the rocker panel protection. I heard or actually read that if you jack this part up on your frame it is very, very expensive to repair.

I say get both but first the rocker panel protection.