This "rotate-version extension cord multiconnect holder" lets you fix the outlet of an extension cord to your multiboard via 1 multiconnect part.
You can print it out of a rigid material like PLA or use something with more flex like ABS, PETG or ABS-like Resin (see foto for a Resin print of the rotate-version).
If you prefer a sturdier version which does not rotate, you can find it here: https://www.printables.com/model/913819-fixed-no-rotation-extension-cord-multiconnect-hold
The author marked this model as their own original creation.