Lifetime Double Garden Box Bracket CUE

I bought 2 3-packs of garden boxes, with the intent to make 3 double-height boxes. Each pack only came with one set of double-height brackets, so I was short one set. I designed these in FreeCAD, and they fit! I don't think that PLA is strong enough, or will last long enough, but it's better than nothing.
The part number is CUE