The Pro Tac SC Gold muff is the premium chop cut cup model of Pro Ears. Designed with a Noise Reduction Rating (NRR) of 25 the Pro Tac SC provides exceptional protection for the loudest environments while still amplifying quieter sounds for improved situational awareness. Constructed ing dual circuit board technology adjt your hearing and amplification levels separately for each ear to compensate for uneven hearing loss ing the dual knob system. Additional adjtment for high and low gain ing internal pin settings. The chop cut allows for easy shouldering of long guns as well as lighter weight. Pro Ears: For the ultimate in Performance Comfort and Reliability.