Review on Zinc Plated Channel Fastener Fasteners - SNAPTOGGLE Toggler by Matthew Oumer

They are not 100% reliable. I've used hundreds of them to hang headboards and curtain valances in a hotel and sometimes the cup wasn't positioned correctly to engage the screw. Even when I tried to tighten the screw before pushing it through the part, there were still moments when it wouldn't turn. Therefore, the holes must match well. I would say about 95% of them worked well. I tried their fakes and they worked much worse. Very good product, just don't expect to need 10 and buy 10. Always buy extra.