 Speaking from experience on that one. All right, that's just a few of the ways. There's also wedge bolts and pin anchors and concrete screw anchors, and then there's some fancy adhesives that you can do for that. But overall, you have to have nice, clean, straight holes for that. No radio-friendly way to say that, I guess. But dust and debris from the concrete will make for a weak attachment or an anchoring, so...