When the electronic ear plug headphone is switched on, it is set at a safe 85 dB sound level and provides protection from loud external sounds while enhancing natural hearing. This allows the ear to hear important commands on the range, and crucial environment sounds when hunting. Eight different volume increments are provided above safe 85dB initial power on level to optimize hearing in the field by providing up to 6X sound enhancement. In continuous noise environments, the device should be used in passive mode for maximum continuous protection. Features: Noise Reduction Rating (NRR): 29dB Separate hear-through volume control Realistic, natural hear-through functions with digital circuitry 9mm Dynamic range speaker 2x Omni-direction in-ear microphones Device actively listens and automatically compresses amplification when loud impulse sounds like firearms discharges exceed 85dB. USBC Rechargable with a charging time of 2 hours Unit Battery Type: 200mAh Lithium Battery Flexible, moldable earhook 3 different ear tips for ideal ear canal fit