These are rock sliders.
These are rock sliders with nerfs
Here are some rock sliders on a Hummer since it's easier to see and maybe to understand for you
Here are rock sliders with nerfs on a Hummer
Exactly, those are LR3 sliders with Nerfs. Now you see my point?
That last hmmvee just has stupid rock sliders, I wouldn't call those "nerfs". If you want to have some fun with it, go search nerf bar on google images. Show me one set of them that are flush with the body.
https://www.google.com/search?q=ner...Q_AUoAg&biw=1904&bih=1105#q=nerf+bar&tbm=isch