Old photo albums, especially ones with adhesive pages or loose prints, are irreplaceable and surprisingly fragile against both moisture and crushing weight. A flat pack and a dry box protect decades of memories in under two hours.
Pro tip: Scan your most irreplaceable photos to a cloud backup before the move if you have not already; it takes an afternoon and permanently protects against a lost or damaged box.
Watch out: Photos and albums exposed to high humidity in a sealed box for extended periods can develop mold spots or stick permanently to adjacent pages.