Removable rigging for helmet

Claim 1

A SAFETY HELMET COMPRISING A SHELL HAVING AN OPENING FOR RECEIVING THE HEAD OF A WEARER AND HAVING A CROWN PORTION TO BE DISPOSED ADJACENT THE CROWN OF THE WEARER''S HEAD, HEAD BAND ELEMENTS DISPOSED AND FORMED RESPECTIVELY TO EXTEND ABOUT AND TO ENGAGE THE FRONT AND REAR OF THE WEARER''S HEAD, A HEAD STRAP OF STIFFLY RESILIENT FLEXIBLE MATERIAL EXTENDING OVER THE INNER SURFACE OF SAID SHELL BETWEEN AND CONNECTED ADJACENT ITS ENDS TO SAID HEAD BAND ELEMENTS FOR SUPPORTING SAID HEAD BAND ELEMENTS IN SPACED RELATION TO SAID SHELL, SAID HEAD STRAP HAVING AN INTERMEDIATE PORTION THEREOF SPACED FROM SAID HEAD BAND ELEMENTS AND EXTENDING OVER THE INNER SURFACE OF THE CROWN PORTION OF SAID SHELL, SAID HEAD STRAP HAVING KEYHOLE SHAPED OPENINGS THEREIN SPACED THEREALONG ADJACENT SAID INTERMEDIATE PORTION THEREOF, SAID KEYHOLE OPENINGS HAVING THE SLOTS THEREOF EXTENDING TOWARD EACH OTHER ALONG SAID HEAD STRAP AND THE ENLARGEMENTS THEREOF DISPOSED AWAY FROM EACH OTHER, AND FASTENING ELEMENTS RIGIDLY SECURED TO SAID SHELL AT THE INNER SURFACE OF SAID CROWN PORTION THEREOF IN A SPACED RELATION TO EACH OTHER ALONG SAID HEAD STRAP CORRESPONDING SUBSTANTIALLY TO THE SPACING OF THE CLOSED ENDS OF SAID SLOTS OF SAID KEYHOLE OPENINGS, SAID FASTENING ELEMENTS RESPECTIVELY PROVIDING SHANK PORTIONS HAVING DIAMETRAL DIMENSIONS TO ENTER SAID SLOTS OF SAID KEYHOLE OPENINGS AND HAVING HEAD PORTIONS SPACED ON SAID SHANK PORTIONS FROM SAID INNER SURFACE OF SAID SHELL, THE DIMETRAL DIMENSION OF SAID HEAD PORTIONS BEING LARGER THAN SAID SHANK PORTIONS, THE ENLARGEMENTS OF SAID KEYHOLE OPENINGS BEING DIMENSIONED TO PROVIDE FOR PASSING THE HEAD PORTIONS OF SAID FASTENING ELEMENTS THROUGH THE RESPECTIVE ENLARGEMENTS OF SAID KEYHOLE OPENINGS, SAID INTERMEDIATE PORTION OF SAID HEAD STRAP BETWEEN SAID KEYHOLE OPENINGS BEING CAPABLE OF FLEXURE TO A FORM CURVING FROM THE PARTS THEREOF ADJACENT SAID KEYHOLE OPENINGS TO THE CENTRAL PART THEREOF BETWEEN SAID KEYHOLE OPENINGS DISPOSED AWAY FROM SAID SHELL, THEREBY TO DRAW SAID KEYHOLE OPENINGS TOWARD EACH OTHER ALONG SAID CROWN PORTION OF SAID SHELL TO POSITIONS TO REGISTER SAID ENLARGEMENTS WITH THE RESPECTIVE FASTENING ELEMENTS AND TO PROVIDE FOR PASSING SAID HEAD PORTIONS OF SAID FASTENING ELEMENTS THROUGH SAID ENLARGEMENTS, THE RESILIENCE OF SAID HEAD STRAP DETERMINING FLATTENING THEREOF FROM SAID CURVED FORM CONCOMITANTLY WITH MOVEMENT OF SAID KEYHOLE OPENINGS AWAY FROM EACH OTHER ALONG SAID CROWN PORTION OF SAID SHELL TO CAUSE SAID SHANK PORTIONS OF SAID FASTENING ELEMENTS TO ENTER THE RESPECTIVE SLOTS AND SAID HEAD PORTIONS TO OVERLIE AND ENGAGE THE HEAD STRAP ALONG SAID SLOTS TO HOLD SAID HEAD STRAP AND SAID HEAD BAND ELEMENTS IN POSITION IN RELATION TO SAID HELMET.