Stackable sorting trays with lids to secure them for storage or travel - This is modular to fit your needs!

I made these mainly to help keep my work space clean and organized with the possibility to expand them as my needs change in the future, but the title says it all. These are based on the "keep is simple stupid" saying.
You don't need to print or use the smallest 1 x 1 squares if you don't need tiny storage. I found that the 2 x 2 trays are the perfect size for most of my needs. Everything stacks together and secures nicely with a lid. The lids can be fixed to the trays with Velcro straps in multiple configurations; one strap around the whole tower, two straps crossed perpendicularly, and even secure a lid on top and bottom with two to four straps around the sides.
The trays come in 30mm unit widths, so the 1 x 1 tray measures 30mm by 30mm, the 2 x 2 tray measures 60mm by 60mm, and so on. This means the 4 x 4 tray and lid will fit on a 150mm print bed. Please let me know if you have any suggestions for improvements.
The author marked this model as their own original creation.