Trivet
Ask any old-timer what this is, and they’ll probably say it’s a metal jacks set. However, without the rubber ball, how do you even get started? Plus, that piece of metal string tying the jacks together isn’t supposed to be there. So, it’s clear that these are metal jacks, but what could they be?
A knowledgeable internet stranger informed the OP that this set is called a trivet. It’s supposed to keep hot pots and pans from scorching your dining table when serving directly from the cooking pot. The string keeps the “jacks” together, but you can place them in any formation to fit any pot.