SureFire earplugs were developed to protect military and law enforcement personnel from harmful sounds. In addition to offering protection, these filtered earplugs allow normal conversations to pass through. SureFire earplugs feature patented EarLock retention rings that provide a secure fit and all-day comfort.Features : 30dB Noise Reduction Rating Patented EarLock Retention Rings Hypoallergenic, Medical-Grade Polymer