A nose-filter was a device fitted inside the nose that protected the wearer against fumes, smokes and pheromones.
Nose-filters were used by Humans traveling through the Orion Colonies, as such as E. D. Fitzgerald. He was hosted by an Orion, Unlot, who represented a company that manufactured nose-filters. Fitzgerald witnessed a human thief stealing a neoheroin cargo fall sick after his nose-filters became clogged, possibly defective. Fitzgerald however used them while experiencing a lengthy Orion banquet, to endure the smoke and the pheromones of the Orion slave girls and avoid neuro-intoxication.