With 9X enhancement and 50 dB of power, these Power Muffs match anyone's hearing needs while protecting them from loud noises. Adjustable frequency tuning (AFT) technology allows you to tune into specific sound frequencies. Sound-activated compression (SAC) reduces loud noises to safe levels. Noise reduction rating of 24 dB. Two independent volume controls offer true stereo sound. Four wind-resistant high-frequency microphones.