Review on Houseables Picture Hanger Kit - Mirror Hanging Hardware, French Cleat, 3 Pair, 6 Inch, 50 lbs Capacity - Aluminum Z Bar Clip Rail Bracket - Wall Mount Hangers with Nails - White Board Mounting, Shelf, Art by Charles Parente

. Problem is they are designed to attach to the frame with a small metal flange which doesn't seem reliable to me. So I drilled holes in the small flange so they will mesh much more securely when assembled. It worked very well, but it took a lot of effort to get to the perfect level. But in the end everything is fine. And if I used them the way they were intended, they might work just as well or even better, but I just didn't feel comfortable (I don't want the paintings to fall over in an earthquake).