The 3M Sport Tactical 300 has a targeted NRR of 24 dB for passive sound protection. Suppresses gunshot noise and amplifies low sounds using proprietary 3M technologies. Dynamic Suppression Time measures the energy in gunshot noise and automatically sets suppression time for reduced echoes and increased comfort. Clear Voice Tracking Technology seeks voice amongst the noise to improve speech intelligibility and situational awareness. Engineered for optimal fit and comfort.