I wanted a better way for my wife to be able to store her Magic: The Gathering cards then some cardboard boxes in a rack, so I bought some IKEA Alex drawers and made a card catalog that fits each drawer nicely, with an emphasis on the trays being accessible and removable without being too heavy.

These are specifically designed to fit 3 rows of cards in the top 5 drawers of an IKEA 9-Drawer ALEX Unit (Like this one: https://www.ikea.com/us/en/p/alex-drawer-unit-with-9-drawers-black-brown-70483434/)

Credit to Zack Freedman for his EXCELLENT Gridfinity system!

Also credit to tinyfluffs for use of their Fusion360 model for the baseplate profile (https://www.printables.com/model/354514/files), and to ismann for his card storage tray inspiration (https://www.thingiverse.com/thing:4604341).