120 Packs 500CC Food Grade Oxygen Absorbers (10 Pack in Individual Vacuum Bag ) , Oxygen Absorbers For Long Term Food Storage with Oxygen Indicator , Works in Mylar Bags, Mason Jars, and Vacuum Bags

The usual advice (cool, dark, dry, no temperature swings) is good, but if you really want to store valuable electronics, do this: Start with a mason jar with a stainless steel lid. Larger items need a bigger enclosure that is just as airtight as a mason jar. Remove any batteries, especially alkaline. Internal rechargeable batteries are usually OK. Wrap the item in unbuffered museum paper. Sometimes know as archival paper. https://www.amazon.com/dp/B0CTRP3Q9D/ Put the item in with several oxygen absorbers and silica desiccant. https://www.amazon.com/dp/B09YDJBYCM/ https://www.amazon.com/dp/B09DSDX4P3/ Store the jar is a cool dark place with minimum temperature swings. Now your watch is stored in a pure dry nitrogen atmosphere with no ozone or ultraviolet. Nothing to degrade the plastic or corrode the metal.