The most recent settlement involving 3M links the manufacturer to knowingly selling defective earplugs to the US Military called the Dual-Ended Combat Arms Earplugs. After paying the US Government $9.1 million, these allegations were resolved, however, the negative effect that these earplugs had on military personnel was not.
It was found that the design of the Combat Arms Earplugs was too short and didn’t provide full protection of the ear canal. As a result, soldiers on the frontlines had an increased risk of hearing damage from loud noises such as gunfire, explosions, and machinery.