u/GiraffeDependant

So I saw this picture a user posted on the sub with their Nilkin case for x300 and have been wondering how ever since (I asked them how but they didn't reply so I thought I might as well ask on the sub). Are they using a step up adapter ring? The filter seems to be the 3 in one neewer filter (probably 67 mm?). Could anyone help me with the dimensions of the step up ring adapter? Is it 52-67 mm? Also, can the filters be directly attached to the Nilkin camshield case? It does have some grooves around the camera cutout, but idk if that means filters can be attached, and if they can, what diameter? 52 mm?

I wanted to use a magnetic cooler for occasional winlator gaming and was wondering what the most optimal position to place the magnetic pad of the cooler is? Here's a teardown video if it helps.