This is a gridfinity base designed for the “Amazon Basics 5-Shelf Adjustable, Storage Shelving Unit, (200 Pound Loading Capacity per Shelf), Steel Organizer Wire Rack, 23.2 x 13.4 x 60 inches (LxWxH)”. I usually buy the 5 shelf variety but assemble it to the height of the 4 shelf (just don't install the small tubes). I've found them very convenient.

This gridfinity base fits the shelf and gives you a 13x7 grid. Most pieces were built just by using the Gridfinity Extended customization tool that I'm making this a Remix of. The corners however needed some customization and were edited with CAD software.

I hope this can save time for people that want to install grids in these shelves, saving them the time to prepare all this themselves.