The Mighty Loud Ear Hearing Enhancer is an affordable, portable personal sound amplifier that helps in one-on-one and small group conversations. Features:Up to 120dB gainBuilt-in microphoneRange up to 100 feetVolume control dial and on/off switchBelt clip attaches to belt or clothingUses 2 AAA batteries for 48hrs of use (included)Dimensions:, 1.75″ W x 2.5″ H x .75″ D