A nose clip is rarely used nowadays for diving, e.g. for apnoea diving. With it, apnoea divers prevent water from entering the nose.
What alternatives to the Nose Clip exist?
For scuba diving though, you would rather use a diving mask with a nose pocket. This keeps water away from your nose. The advantage in comparison to the clip is obvious. Here the equalization is more secure and no negative pressure originates in your throat-nasal cavity.
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