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 AMS active support shaft assembly that fits in any of the drawers that is at least 4u high. The model includes 4 different sizes, 1x3x4u, 1x3x6u, 1x3x8u and 1x3x10u.
Please have a look at the assembly model(here) for more information