FOSBOS is an completely free organizational system, every model is open sourced including both fusion 360 file and the step file. All the drawers are designed after the gridfinity standard.
This model is a bin for storing your XYZ belts that fits in any of the drawers that is at least 2u high. The model includes 5 different sizes, 2x2x2u, 2x2x4u, 2x2x6u, 2x2x8u and 2x2x10u.
Please have a look at the assembly model(here) for more information