OMER Umberto Pelizzari M1 Low Volume Freediving Mask

The volume of air inside the mask, between the face and the lens, represents the internal volume.
For freedivers and spearfishers, the internal volume of the mask must be as low as possible to make it easier to equalise.

The mask is pressed against the face when diving. As you dive underwater, pressure is applied to the mask's soft skirt, reducing the internal volume and pressing the mask against the face. This phenomenon, which can cause pain in the eyes, can be avoided by equalising the internal pressure of the mask and the external pressure applied by the water. To do this, simply breathe out gently through your nose. Air is very precious in underwater sports, so equalisation should be kept to a minimum.