The PO took them off. The holes are there but I only found one bolt, not too fond of them but I wanna put them on. Are they just bolted on? Nut / bolt?

And what's the deal with these anyway? Was it just a fancy factory option?

I had the overrider. There was a very minor fender bender, the overrider rotated around it's attachment to the bumper and embedded itself into my hood. Maybe it would help in some situations but without it I would have had just a dented bumper - the hood would still be OK and I would have saved a bunch of pounding, bondo, 4 spray cans of high-build primer etc. Hate the overrider.