Outgrowing my 1st humi, I had extra beads (the humi had come w/beads and I'd ordered more) and needed to set something up for a tupperdor. Punched holes in an aluminum cigar tube (La Aurora) with a push pin, add beads and distilled H2O. Voila. Worked perfectly. Until I outgrew that. Now I have a cooler. But the tube worked well because it fit well. Only needed enough beads to fill the larger half to @ 1/4" from spilling over when open.