The Voice Clarifying Over Ear Amplifier with Charging Case This is the over-ear digital earpiece that amplifies and clarifies voices. Its advanced microchip detects incoming sound levels and provides continuous volume regulation while its noise-free setting filters out low-frequency background interference, making spoken words clearly audible. A second setting disables the filter, ideal for amplification when in nature or in an otherwise quiet environment. With a microphone that picks up sounds within a frequency range from 1,200~1,600Hz, the amplifier provides optimal sound levels to a maximum 25dB gain, ideal for meetings, television, or auditoriums. Its rechargeable battery provides up to 12 hours of operation from a seven-hour charge using the included carrying case, which includes one AA battery; also recharges in five hours via the included AC adapter. Includes three differently sized silicone caps to accommodate all ear canals. 1 1/2" L x 1/2" W x 3/4" H.