Fixing plug

Claim 1

A WALL PLUG, COMPRISING AN ELONGATED TUBULAR BODY OF COMPRESSIBLE SYNTHETIC RESIN MATERIAL OPEN AT OPPOSTIE EXTREMITIES AND FORMED WITH A SMOOTH-SURFACED INTERIOR SURFACE AND WITH A PLURALITY OF LONGITUDINALLY SPACED ANNULAR CYLINDRICAL EXTERNAL SURFFACES SEPARATED BY ANNULAR FRUSTOCONICAL EXTERNAL SURFACES CONVERGING SEPARATED BY ANNULAR RESPECTIVE CYLINDRICAL SURFACES, EACH OF SAID FRUSTOCONICAL SURFACE TERMINATING AT THE BEGINNING OF A NEXT-ADACENT ONE OF SAID CYLINDRICAL SURFACES TO PROVIDE A RIGHT-ANGLE SHOULDER THEREBETWEEN, SAID BODY HAVING A LEADING END AND A TRAILING END AND BEING PROVIDED WITH A BORE EXTENDING FROM END TO END AND WITH A PAIR OF THROUGHGOING DIAMETRICALLY OPPOSITE LONGITUDINAL SLOTS LYING SUBSTANTIALLY IN A FIRST DIAMETRAL PLANE THROUGH SAID BODY AND A RESEPECTIVE PAIR OF RESILIENT DIAMETRICALLY OPPOSITE ARCUATELY CONVEX PROJECTIONS ON EACH OF SAID CYLINDRICAL SURFACES DIVERGING IN THE DIRECTION OF SAID TRAILING END AND LYING IN A SECOND COMMON DIAMETRAL PLANE OF SAID BODY PERPENDICULAR TO THE FIRST-MENTIONED PLANE, SAID PORJECTIONS HAVING RADIAL THICKNESSES DECREASING FROM THEIR JUNCTION WITH THE RESPECTIVE CYLINDRICAL SURFACE AND HAVING UPPER SURFACES CONSTITUTING SUBSTANTIALLY CONTINUATION OF THE RESPECTIVE SHOULDERS, SAID SLOTS TERMIANTING SHORT OF SAID ENDS TO PROVIDE CIRCUMFERENTIALLY CONTINUOUS END PORTIONS OF SAID BODY, SAID BODY HAVING AN ENLARGED HEAD AT SAID TRAILING END.