I'm not trolling. I didn't know whether it would rust or not.
Obviously a huge issue for the tens of thousands of snowboards out there, pretty much all of which have multiple insert holes open/uncovered...
I was actually somewhat hoping that this was a trolling attempt, because the idea that somebody from a younger generation would ask this as a serious question fills me with dread for the future of this country/planet.
Looks to me like itís aluminum, which doesnít rust.
To be fair, not everyone can recognize metals, especially younger folks with less experience (or less interest) in them. We use many different metals at work, and I still sometimes have a hard time telling some of them apart...
remember this as well as every other insert on your board is exposed to the snow and water and they are just fine. So with that the inserts that won't be used should be just fine as well.
I run a tap into the threads of my all my inserts on every brand new board to clean out any glue residue from the building process. I also clean them out 2x a year. The end of the season when they go into storage and mid season just in case I want to make a binding adjustment. I usually don't move them now that I found the sweet spot of where I like them, but I still clean them out.
If you are so concerned buy yourself a tap and clean them out when you wax your board for your piece of mind