” a strategic supply of canning jar lids”
About 2009 when I got into prepping, I wondered how to store metal lids so the rubber lasts. Never figured it out or did anything with the lids, so I hope they still work.
I just leave them in the box. It’s oxygen that makes things deteriorate so if the oxygen is kept down, it should be a problem.
Also, when I buy lids, I date the box with the purchase year and constantly rotate my stock. Never had a problem with them.