Walker's Digital AM/FM Radio Power Muff. Built-in Radio with Switch Key and Volume adjusting key. Channel memory function, (8) eight different preset channels. Digital display screen with Low battery indicator. Input Jack for MP3. Auto search and frequency scanning function. Built-in antenna with high reception sensitivity. Extra wide headband with soft padding. Power source 2 Alkaline ""AAA"" batteries. Noise reducing rating NRR25dB.