They are called different names among manufacturers but everyone knows them from washing machines, fridges, cars and so on:
Where can I find an insulated piece where you can plug three or more of such connectors together without it having to be bolted to something? IOW a link hanging in the air. With the insulation skirting down far enough so it can't short out against other metal stuff. I have seen them but can't remember where, I checked Wago and the usual suspects but came up dry.