How did 3M's defend itself in this case?

What do you think about this case? (Eg: Who should take more responsibility, 3M or U.S. military? Do you think the settlement is fair enough?)

Asserting that all claims are preempted by the "Feres" doctrine

In my opinion, both 3M and the U.S. military share responsibility in this case. 3M know that they sold defective earplugs to the military, putting soldiers at risk. However, the military also has a duty to ensure the safety of its personnel and should have conducted more thorough testing and oversight of the earplugs.

3M has argued the CAEv2 earplugs are not defective by design and only fail to work when they are not worn properly. On its website, 3M states the CAEv2 earplugs are a "significant innovation in hearing protection," and the company defends the safety and effectiveness of its product.

3M defended itself by arguing that the Combat Arms earplugs were not defective and did not cause the hearing damage claimed by the plaintiffs. They also attempted to use the “government contractor defense,” which would have shielded them from liability by asserting they followed government specifications.

Both the manufacturer and the military have a duty to ensure the safety and effectiveness of equipment.