Just a double size bin for carrying larger hardware/parts.
Check out my other post for the nesting bins for the original organizer bins.
https://www.printables.com/model/738836-toughbuilt-stacktech-organizer-2-3-tier-nesting-bi
Disclaimer: Some small hardware may spill out of bin when carrying organizer like a briefcase.
The author remixed this model.
Adjusted dimensions to fit Stacktech Organizer.