A 104.5mm x 112mm x 22mm tray that will hold and organize 20 swatches - https://www.youmagine.com/designs/filament-swatch
There is built-in "wiggle room" to help the swatches slide in and out of the tray with greater ease.
Available with and without a debossed label of the material type that the swatches are printed from. (Right now I have one with PLA, but as more filament finds its way into our school makerspace, more debossed labels will be added.)
UPDATE 2021-05-08 - Two more trays added... one for Tough PLA, and one for "Out of Stock" (At least until we reorder more of it :-)
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