The two models here are the “top” and “bottom” anchors for https://www.printables.com/model/494691-3d-printed-cable-management-spine

These models are designed to accept a “mid thread” and screw into a snap in Multiboard.  Photos include two 10mm Flat Head Mid Thread bolts from Multiboard.io

https://thangs.com/designer/Keep%20Making/3d-model/10%20mm%20Mid%20Thread%2C%20Flat%20Head%2C%20Bolt-973845