24dB* Noise Reduction Rating (NRR) with stoppers inserted * Lowers potentially dangerous noise levels above 85dB * Hear safe sound levels (with stoppers out) as if you weren"t wearing ear plugs * Ergonomic design and triple-flange stem design conforms to ear shape for comfort and secure retention * Low-profile design allows you to keep them in place while wearing a mask, helmet, hat, or while using phone, headphones, or supplemental hearing muffs