10 in. x 8 in. Oil-Rubbed Bronze Heavy Duty Shelf Bracket

I used Tapcon screws into a concrete wall to hold a heavy UPS power supply. It worked like a charm. Just make certain the screws will fit through the holes in the bracket.

This shelf bracket is recommended for indoor use. Exterior use may cause rust and corrosion, thus weakening the bracket over time.

We do not recommend mounting the shelf under the bracket. The long leg should be attached to the wall with the short leg to support a shelf (shelf on top of bracket) will be stronger, working weight limit is 1200 lbs. per pair in 16” apart.

Yes, the bracket can be used with the 10" side against the wall with the 8" side under the shelf.

You can install any size of top flat surface (e.g., plywood, mdf, etc.) with the brackets as long as you stay within the weight capacity of the brackets and install the brackets on the stubs. I believe the shelf should have no problem holding your boxes.

Yes, this bracket can support a granite countertop backed by wood.

Yes...they support a LOT of weight!!!!

I put up three shelves, all 5' by 12" by 1". I used three brackets per shelf. I am using these shelves for plates and ceramic cookware. The ends of the shelves are bending JUST a little. If I was to do it again, I would have used 4 brackets per shelf to avoid the bending on each end, but the brackets are holding up the shelves beautifully considering the weight that is on each of them. I DID make sure that the brackets were drilled into studs.

Yes it depends on what you anchoring to. They are heavy duty

The manufacturer notes that the max. distance of two brackets is 26”. For the 7 foot length they recommend installing 4 brackets, leave 3 inches at each end and 26” in between the 4 brackets.