The SUREFIRE EP4 Sonic Defenders Plus features filters that reduce noise by 24dB, effectively blocking out surrounding sounds. It is particularly well-suited for use in noisy environments. The patented EarLock retention ring securely holds the earplugs in place, and the adjustable stem conforms to the shape of the ear. They are comfortable even during extended use. The filters are designed to reduce ambient noise while still allowing you to hear conversations, enabling you to maintain necessary communication. - Brand: SUREFIRE - Model: EP4 - Size: L - Noise Reduction Filter: 24 dB - Patented EarLock: Yes - Adjustable Stem: Yes - Suitable Size: Medium (less than 1 inch)