Review on Set of 4 Heavy Duty 12-Inch Frosted Black Wall Brackets with Lip for Floating Shelves - Rustic Iron Metal Shelf Brackets for DIY Open Shelving, Including Hardware by Mark Quarterman

We installed them for a bookcase set and they are NOT heavy duty at all. The brackets themselves flex very easily, just press on them. Even with a wooden shelf mounted on a bracket, the whole thing sags nearly two inches under the pressure of a finger (we installed four brackets for 10-foot pine shelves, which should be an exaggeration). It's not the shelf that bends, it's the brackets themselves. BREATHTAKING. I'm very frustrated because now I have to find time to find something new. If this shelf were filled with books, the brackets themselves would not be parallel to the floor, but would lean forward. Really disappointed.