Walkers ultimate power muff features high gain omni-directional microphones and 9x hearing enhancement with 50 db power.It has aft with two independent volume controls, sound activated compression, and an nrr of 26db.The ultimate power muff features a compact, folding design with anti-microbial ear pads.It operates on 2 aaa batteries (included).The quads model has four microphones.Type: Electronic EarmuffColor: Black Ear Cups w/Black BandNrr: 26 dBQuantity: 1 PairStyle: Over the HeadAft Circuit: YesBattery: AAACompression Circuit: YesMaterial: Polymer