A piece sized to fit the bottom of a particular coffee bag, just undersized at 82mm x 56 mm. A hole on the top fits a ¼" bolt to attach the shoe to a rod.

I made this for my wife's coffee roasting work - when filling bags, they needed to stick their whole arm into the empty bags to get the bottoms flattened out. This mounts onto a one-inch dowel, and allows bags to be pulled over top to make this part of the process slightly easier.

Find the OnShape design here, where you can tweak the shoe to your bag size.