Standoff posts for mounting printed circuit boards outside of cases.
I have one of the FTDI EVE F800B boards and I wanted to do some software for it but I don't have a case. These standoffs have a small pilot hole in them, I used a #43 drill to drill it out so that I could 'tap' in some 4-40 BHCS machine screws to mount to the display. Some more of the same standoffs are used to mount a Nucelo board (the processor side) next to the display board.
These have become quite useful for me, I've printed over 24 of them. In this update I've included the "fat" standoffs which include a fillet between the standoff and the base which gives them better strength. In using them I've noticed sometimes if you hit them at an angle and were using PLA or PET filaments, the standoff would break off the base. The fillet fixes this.
General usage is to use a 4-40 (or M2) machine thread bolt and to go through the PCB into the standoff. There is an internal tube printed (shown in the drawing) which is there so that there is solid plastic to hold the threads. Depending on your use of walls you may be able to use the hold directly or you might need to widen it slightly (a #143 drill is the standard hole for #4-40)
You can then just put the board on the table at that point on its new "legs" however, if you have multiple boards, and you need to keep them in position relative to each other, then first attach standoffs to the board. Second arrange the boards as you would like on a piece of poly carbonate or acrylic. Finally put a drop of cyanoacrylate (superglue) on the pads and stick them to the board.
You can now unmount the boards by unscrewing them and remount them again as needed while keeping their arrangement.