Bit silly to call one part or the other the correct part to unscrew. Not like it came with any kind of instructions on how to use. Why even thread it in two places if you’re not meant to undo one? Or put some red locktite, etc etc
The piece I unscrewed is clearly rolled (for grip, like a barbell, why else?)
The piece I unscrewed is clearly rolled (for grip, like a barbell, why else?)