How can I join 20“x20”x1" panels into a one-end-open box?

This is an attempt to ask a more-focused version of a prior question (How best to join (in reversible manner) 5 20"x20"x1" panels (4 air filters, 1 plywood) into open-ended box?), that was closed with the suggestion to "focus on one problem only".

I have 5 20in x 20in x 1in panels of lightweight material. (You can think of it as identical to the foam-insulation boards, sold in nominal 8ft x 4ft x 1in panels – as one or more of the panels will actually be cut out of such a board.)

I’d like to join them along the edges to make a cube that’s open on top. Of course something like tape is one sloppy option, but I’m hoping to find a superior option that holds them rigidly and tightly in relation to each other, but is reversible, so sides can be individually replaced.

(More specifics about the intended home-air-improvement application of this box are in the original closed question, but my focused need here is to solve the home-insulation-materials joining problem.)

Is there a solution meeting the above parameters?