Caster adapter for wire storage rack

I wanted wheels on an Amazon basics wire shelving unit and had some extra office chair casters (11mm stem), so enter this adapter. It uses the screw-in feet that come already attached to the shelving unit which snugly fits into a matching shape on the adapter. In the end you wind up with a caster that screws in just like the foot.I intentionally made the fit tight so no adhesives are necessary on the caster end, you will need a standard hammer:- Put the shelf foot into the adapter first, tapping the end of the thread and the body of the foot until it's all the way in. It will probably take a couple tries to line it up right. You may want to use epoxy or a strong adhesive for this connection, the foot can stress the adapter and tilt out of it if there's enough weight - see the important note at the bottom.- Next, start the caster in the other end. You will need to hold the caster in place and again hammer the end of the thread to get the caster fully inserted, and it may take so