From Pathfinder Lost Omens Highhelm, which isn't enabled.

Everair Mask (Major)

ITEM 14

Price 625 gp

Usage worn mask

Bulk L

This simple, mass-produced gaiter mask is standard issue for miners working in deep, dangerous mines. While wearing the mask, you gain a +1 item bonus to Fortitude saving throws against inhaled poisons. An everair mask makes use of magical runes related to the Plane of Air to create breathable air.

Activate envision, Interact

Frequency once per day

Effect You activate the mask's rune, and the air surrounding air, as well as the air you exhale, becomes enriched with oxygen. This allows the everair mask to recycle air into breathable air for 24 hours. The rune's magic is unable to provide breathable air while underwater, in a vacuum, or in any other situation where air is normally unavailable.

Pathfinder Lost Omens HighhelmOGL