I'd like to make a robot lamp like this one: Yes, I've seen this question. Also, I'd make it myself (not buy it). Anyways, can anyone identify the part that the bulb screws into? I know it connects to a knockout, but what is it. Yes, I fully intend to ground it, and I certainly know to NOT connect the exposed prongs

Not sure... Might want to start a question, chat is probably not the best place for that (and has very few users / low activity). Do you have a higher res picture?

@Criggie Yep, it would be mains-wired. But I will (most likely) use a garbage disposal cord to power it as it both includes ground and has a clamp to make it easier to connect to the box. If those are 12v that might be an issue. I could also make one like this instead:

I'll go post a real question though

imgs.search.brave.com/…

12V would be safer, and less heat output. You could choose to use LED lamps instead of incandescent too, but that's a different appearance.