Never have seen anything quite like these. They aren't divots, they're a round-headed nut on the outside and what seems to be a three-prong head (sort of like a crows foot) for the screw on the inside. Tough as nails. I figured I'd just take a cut off wheel and knock it down. Wrong! I can't see the screw head part, but the nut is a half round type thing.
Any assistance would be appreciated
Jim
Any assistance would be appreciated
Jim