The anchor fell apart with the slightest manipulation, and even Zeus himself would be lucky enough to put it back together. Update: Thought I'd use at least one of them. I bought a 16mm chisel, drilled a nice hole, cleaned it and started driving the anchor. Halfway through, it became clear that this anchor wasn't up to the task. I continued to play softer shots. In the end it was completely deformed (see second photo) and no longer fit on the screw. I have no idea why this product has so many good reviews - I feel cheated.