I had a stained glass window that I wanted to hang in the window. I carefully weighed the piece (1.6lbs) and looked for a hook that could handle that weight. They're supposed to hold 6.6 pounds, so I had to be absolutely sure. I hung it on a hook and after about 2 hours I heard a loud crack and it fell, so it's obvious the hook couldn't handle the stated load capacity. I've redid it with both hooks and it's now holding up well for over 24 hours so it seems secure (although I still have padding underneath because I was lucky it didn't break the first time and I didn't want it to break when it falls again). So make sure you don't expect to actually carry 6.6lbs of weight as one hook doesn't even seem to hold a little over 1.5lbs.