Littmann hearing aid: with distinguished sound systems: where the highest sound systems are available in Littmann automatic medical hearing aids. • The membrane covering the chest piece can be adjusted to help listen to sounds whether high or low frequency by slightly adjusting the pressure on the chest piece. • Double cavity tube: where this tube contains two sound paths; which reduces the usual friction noise in the double tubes. • The headgear is easily adjustable to provide the appropriate size and comfort for each individual, and features curved ear tubes that fit the ear canals. • Includes a special tool to help hear sounds when examining children and newborns.