The Safariland Pro Impulse Hearing Protection offers superior noise-blocking, achieving an impressive NRR rating of 33dB in a high-grade, reusable ear plug. Safariland's ear protection is easy to insert and is comfortable to wear, even in long settings. The patented Impulse Filter Technology suppresses those dangerous levels while allowing normal ambient audio to flow through. This is highly beneficial when you still want to be part of the conversation at the range. Automatically engages to protect hearing Allow ambient sound to pass through Proprietary material for long wear comfort Includes high-quality aluminum transport/storage case keychain No batteries required 2 sizes of ear inserts included (1 pair of filters)