3M Peltor Tactical 6-S Slim Line Electronic Headset with Audio Input Jack, Olive Green, Hearing Protection, Ear Protection, NRR 20 dB, Great for hunters and shooters Noise reduction rating of 20-dB Slim line, folding headband for compact storage Ambient listening electronics provide distortion free amplification of low level sounds up to 14-dB Individual on/off and volume control knob 4 AAA batteries (2 per cup) for over 300 hours of operation