A nasal device for filtering breathing air comprises an elongatedsupport member, and two rounded holder members, each arranged ata respective end of the elongated support member. The holder members areadapted to be inserted into a nostril with a distal end directed into thenostril,and a proximal end adjacent the nostril openings. The holder memberscomprise a bell-shaped cross-section in at least one plane in a distal-proximalextension.
