The silencer is intended for discharging air from diving tanks. Anyone who has had to discharge  leftover breathing mix knows what a problem it is to keep the hiss of the released air to a reasonable level even during relatively slow discharge.

The silencer is attached to the tank valve and the gas can then be discharged within a few minutes, even in a closed room or onboard a boat, for example. Thanks to this effective silencing, noise does not exceed a level that would make conversation difficult in close proximity to the tank.