Reusable Hearing Protection with Automatic Engagement FilterSafariland TCI Pro Impulse Hearing Protection is designed to reduce loud noise while still allowing ambient sound to be heard. These reusable earplugs offer an NRR of 33 dB and feature an ergonomic contoured shape for easier insertion and long wearing comfort. Automatic engagement filter technology helps protect against loud noises such as gunfire and explosions. NRR 33 dB protection Reusable earplug design Allows ambient sound Automatic engagement filter technology Ergonomic long wearing comfort