An external nasal dilator comprising a truss, the truss including: a first end region adapted to engage the outer wall tissues of a first nasal passage and a second end region adapted to engage the outer wall tissues of a second nasal passage; an intermediate segment connecting the first and second end regions (16,18), having a width less than the width of the first and second end regions, and configured to traverse the bridge of the nose located between the first and second nasal passages; a flexible strip of base material defining the first and second end regions (16,18) and the intermediate segment; a resilient band secured to a first side of said base material; a biocompatible adhesive substance covering the entire second side of the flexible strip of base material for removably engaging the dilator to the nose of the wearer; wherein the truss including the flexible strip of base material, resilient band and adhesive is slotted inwardly by inward slots (26a, 26b) from both lateral ends, terminating short of the intermediate segment thereby dividing the truss into four resilient branches (28a-28d) comprising two lower branches (28b, 28d) and two upper branches (28a, 28c), characterised in that: the resilient band traverses the entire length of the first side of the flexible strip of base material to the ends of the truss, the inward slots (26a, 26b) are of equal length and have opposite side edges (36a - 36d) which are parallel, the resilient band has inner edges which extend to the side edges (36a - 36d) of the inward slots (26a, 26b), the resilient band has outer side edges which are parallel to said inward slot side edges (36a - 36d), and the base material extends beyond the outer side edges of the resilient band to external edges (38a-38d) adjacent the end regions (16, 18) to comprise extended tabs (40a-40d). a first end region adapted to engage the outer wall tissues of a first nasal passage and a second end region adapted to engage the outer wall tissues of a second nasal passage; an intermediate segment connecting the first and second end regions (16,18), having a width less than the width of the first and second end regions, and configured to traverse the bridge of the nose located between the first and second nasal passages; a flexible strip of base material defining the first and second end regions (16,18) and the intermediate segment; a resilient band secured to a first side of said base material; a biocompatible adhesive substance covering the entire second side of the flexible strip of base material for removably engaging the dilator to the nose of the wearer; wherein the truss including the flexible strip of base material, resilient band and adhesive is slotted inwardly by inward slots (26a, 26b) from both lateral ends, terminating short of the intermediate segment thereby dividing the truss into four resilient branches (28a-28d) comprising two lower branches (28b, 28d) and two upper branches (28a, 28c), characterised in that: the resilient band traverses the entire length of the first side of the flexible strip of base material to the ends of the truss, the inward slots (26a, 26b) are of equal length and have opposite side edges (36a - 36d) which are parallel, the resilient band has inner edges which extend to the side edges (36a - 36d) of the inward slots (26a, 26b), the resilient band has outer side edges which are parallel to said inward slot side edges (36a - 36d), and the base material extends beyond the outer side edges of the resilient band to external edges (38a-38d) adjacent the end regions (16, 18) to comprise extended tabs (40a-40d).