Targeted NRR of 26 dBA for passive sound protection. Suppresses gunshot noise and amplifies low sounds using proprietary 3M technologies. Gunshot Recognition and Suppression Technology optimizes noise protection based on the firearm being used and the environment in which it's being used. Clear Voice Tracking Technology seeks voice amongst the noise to improve speech intelligibility and situational awareness. Bluetooth Wireless Technology to seamlessly sync to mobile devices. Make and receive phone calls through the headset. The replacement gel ear cushions can be used to replace worn or damaged rings or provide enhanced comfort when wearing hearing protection. Easily clicks into place to extend the life of your 3M Hearing Protector. ALPHA1100 litium-ion battery package includes USB cable and battery pack.