This is a Surefire Ear Plug known as the Sonic Defender, model EP3-MPR.
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:
24dB Noise Reduction Rating
Patented EarLock Retention Rings
Hypoallergenic, Medical-Grade Polymer