Autoclavable Nasal Hoods, Double Mask Hood Kit, with 3 Inner Mask Liners, Pediatric, 1/Pk. Double Mask Nasal Hoods present a reusable and autoclavable two-layered scavenging material for nitrous oxide sedation. Their soft, pliable silicone structure fits accurately around the nose for improved visibility to the operative field and a fastened seal.