Abstract: A device for improving flow of air through a nasal cavity of a wearer during activity such as cycling or running or like exercise substantially minimizing air flow resistance, the device including a substantially U-shaped body forming a bridge for spanning adjacent nasal cavities of a wearer; a first adjustable body and a second adjustable body mounted to opposite upright portions of the U-shaped body, the first and second bodies each having: a belt adjustable about an attachment mount on an upright portion of the U-shaped body; a rib extending outwardly and arcuately from a portion of the U-shaped body distal to the bridge, the each rib ending in a relatively large surface area portion connected to a portion of the belt, the large surface area portion of the each rib adapted for abutting internal wall surfaces of the nasal cavity of a wearer, and wherein the belt and rib form an open channel defining an air flow pathway within the nasal cavity; and whereby in an operating condition the belt or belts is tight