1x3 Gridfinity box with a hexagonal wall pattern.

I balanced the pattern of the wall to achieve maximum strength, elasticity, and perspective.
There is space at the bottom for placing a standard 6x2mm magnet in each corner.

Here's my collection of Grifinity boxes. If you can't find the size you need, feel free to ask for it.
https://makerworld.com/en/@LeviMoore/collections/1789900