These are height adjustable anti-vibration feet for Ikea Lack Tables. Each foot consists of two printed parts and a JB6368 anti-vibration pad that slips on the end. The female part is attached to the table leg and has internal threading. The male part has external threading, holds the anti-vibration pad, and screws into the female part which allows height adjustment to level the table.
Amazon - JB6368 Anti-Vibration Pads
Translucent Royal Blue
No support is needed for the female piece, but for the male piece, enable support from build plate only. There is a lip near the bottom that sits on the top of the rubber feet to try and maximize surface contact.
Mount a female part on the bottom of each leg with four (4) screws. It helps to hold the part in place and use a marker to outline one hole, remove the part, and use the marking to get a hole started with the screw. After a couple turns, remove the screw, place the female part back on the leg end, and now you have a nicely oriented pilot hole to get you started. The rest of the screws shouldn't be a problem now with the part pinned down.
Attach an anti-vibration pad to all male parts and screw each one all the way into a female part. Put the table back where it belongs and unscrew any legs that aren't in full contact with the ground to level the table.