Personal Sound Amplifier. The most affordable with best quality hearing helper. Behind The Ear, Easy To Use, Clear Sound, Fit Both Ears, Energy-Saving Technology, with 4 ear buds (Large, Medium, Small and Mini) to fit most customers. New flexible tube best fit over ear. Ear buds made from special soft rubber that’s comfortable. One LR44 / 357 / 76 button cell battery included(20 hours). PR44 / 675 button cell battery available for purchase separately (100 hours).