This is a Multiboard's compatible bolt for the small thread. It is printed split to maximize its strenght. It can be used to attach objects to the multiboard.

These bolts are meant to be used instead of the T-bolts from multiboard.

There are two lengths: 9mm and 12mm. The size of the head allows for a ½ inch wrench (use a socket one).

if there is interest, I'll upload other lengths.

This design is not a derivative work of Multiboard models.

Thanks to Dave D for this documentation of the threads: https://www.printables.com/model/709777-multiboard-screwbolt-step-files-for-modeling

I have uploaded a non-split version: https://makerworld.com/en/models/801155#profileId-741176