Lotos reveals for the first time what is required of a rugged and hard-wearing hearing instrument: Lotos is hermetically sealed and can remain under 1 metre of water for 10 minutes without problem and without any impairment. Serviceability under severel conditions means hearing convenience for all those who must work in extreme weather conditions. Or those who are keen on water sports or who do not wish to forgo strenuous mountain walking. As a result of its strenght, the instrument is less susceptible to breakdown, and therefore not the least of its features makes it ideal for children. The sealing of the two-section casing and of the battery compartment and trimmer cover is provided by profile and labyrinth seals. Receiver and microphone tubes are provided with flange-shaped protuberances which hermetically seal the instrument against moisture on fitting the earhook. A watertight diaphragm has been fitted in front of the microphone, while the switching elements are protected by precise sweat-proof and light-fast rubber seals.