Valsalva device

Pad in a helmet or mask used to block the nose to assist in ear clearing

The Valsalva device is a device used in spacesuits, some full face diving masks and diving helmets to allow astronauts and commercial divers to equalize the pressure in their ears by performing the Valsalva maneuver inside the suit without using their hands to block their nose. Astronaut Drew Feustel has described it as "a spongy device called a Valsalva that is typically used to block the nose in case a pressure readjustment is needed."

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