DTMCare Digital Rechargeable Hearing sound amplifier for right ear and left ear (FDA Approved) Re-charged by AC adaptor or one AA Battery, no hearing battery needed. Special made for right ear and left ear. Volume control on the side, easy to adjust. Delay function to avoid feedback noise. Max. output sound level gain: 50+-5 dB, super clear sound. 4 different size of ear buds (L, M, S and XS). One year warranty. New flexible tube best fit over ear. Ear buds made from special soft rubber for comfortable.