Lineco, Herbarium Mounting Paper, Archival Quality, PH 8.5, Acid-Free, Cotton Rag Unbuffered Material for Institutions and Museums-11.5x16.5 inch, 0.015'' Thickness- Pack of 25

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.