Atmospheric Stabilizer is a triangular gadget that allows the user to breathe at extremely high altitudes - though only in small, contained spaces. Keefe, Biana, and Fitz used these in Book 3: Everblaze when at the battle on Mt. Everest. She goes there after Grady's fight with Brant, and she is extremely cold and almost passes out. Luckily, Mr. Forkle finds her in time, and gives her an atmospheric stabilizer while she's in the cave. Then, when fighting with the ogres, Sandor gives Sophie his. Goblins don't have as much trouble breathing at high altitudes.