anyone know?

[f5fstop]

Maybe it's me, but on the top it looks like marks from a socket, and if the witness marks are on the left side, that means a socket removed it. Again, it might just be me.
But, KenP is also right, it does look like a caliper bolt, but could be used for other suspenion part too.

[H3HUMVEE]

I read another post somewhere about H3 caliper bolts coming lose .. not sure if it was on this forum ...