The head of the screw is on the inside of the metal frame and it screws directly into the shelf bracket on the outside of the frame. You don't need any nuts because the bracket on the swivel shelf is internally threaded.I just got my hands on a set of Jerker printer arms but they came without screws. I can always go to home depot and get some, but I have no idea how you screw them in. Do they go from the outside of the arm into the frame? Can someone post a picture or explain how it works?
Shitty photo for reference:
These are the screws you want: