High security fastener with external shroud retainer

A method of forming a fastener comprising the steps of:

• providing a fastener body orientated about a central axis;
• said fastener body having a tool engaging portion to which a driving torque may be applied, a threaded fastening portion configured and arranged to mate with corresponding threaded element, and a shroud-receiving body portion orientated about said central axis;
• providing a shroud;
• mounting said shroud concentrically in said shroud-receiving body portion such that an outer surface of said shroud faces an inner surface of said shroud-receiving body portion;
• axially aligning an outwardly extending annular shoulder of said shroud with a deformable rim portion of said shroud receiving body portion;
• restraining said fastener body from moving in a first direction along said central axis;
• applying an axial force to said deformable rim portion of said shroud receiving body portion such that said deformable rim portion of said shroud receiving body portion deforms inwardly under said applied axial force to form an inwardly deformed stop radially overlapping said outwardly extending annular shoulder of said shroud;
• and
• such that said shroud is restrained from movement in at least one axial direction along said central axis;
• and
• such that said shroud is permitted to rotate about said central axis relative to said fastener body under an applied external torque prior to said fastener body rotating when said fastener body is engaged with an external structure at a design installation torque.