The Rifleman ACH is an electronic hearing protector that offers strong protection with an NRR of 21 while delivering quality sound. The unit weighs only 8.3 ounces and folds for easy storage. Ideal for outdoor use, the ACH has a slim headband and can be easily worn with combat helmets and other hats and headgear.Seperate ear controls to fine tune amplification. Input jacks are on each cup .Use four (4) AAA batteries (not included).