Which packaging innovation was initially developed for military use during WWII and later revolutionized civilian product packaging?

Throughout military history, packaging innovation has played a crucial but often overlooked role in warfare success. From food preservation for long campaigns to ammunition protection in harsh conditions, military packaging has driven technological advances that later influenced civilian consumer products. This trivia question explores a significant packaging innovation that revolutionized field operations and later transformed civilian product packaging.

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Aerosol cans (developed to spray insecticides in the Pacific Theater)
Vacuum sealing (developed for preserving medical supplies)
Aluminum foil packaging (developed for high-altitude ration drops)
Blister packaging (developed for tropical-environment ammunition storage)