Kaukau Nuva

The Kanohi Kaukau Nuva was the Kanohi Nuva Mask of Water Breathing. Like all Kanohi Nuva, it could only be used by Toa Nuva. It enabled the wearer to breathe underwater almost indefinitely, even at extreme depths.

Most of the Kanohi Nuva were created in Artakha and teleported to the island of Mata Nui for the Toa Nuva to use. Each Toa collected one of each type of mask, however, upon entering the Universe Core, they lost the ability to use the masks they had stored on Metru Nui due to Karda Nui's shielding. As such, Toa Gali Nuva was the only one still able to use her Kaukau Nuva, as she was actually wearing it.