Abstract: A flexible hose of a self-supporting material formed by helical revolutions of an interlocking strip. The strip includes a tongue, a groove, and an interconnecting integral wall. The groove is formed by a receptacle having an internal cavity for receiving the tongue as the strip is helically wound upon a mandrel. The internal cavity is provided with a void for receiving an adhesive or weld. The placement of the adhesive or weld within the void determines whether the hose is more suitable for vacuum, high pressure, or maximum strength use. The configuration of the strip is such that the finished hose has a smooth, relatively uninterrupted internal surface. The cross section of the strip is substantially uniform throughout, has a groove that not only renders the assembled hose capable of taking a sharper curve without collapsing, but also can receive a ground wire for use in grounding the hose, and is easier and cheaper to extrude since it uses less material.