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Claim 1

A MULTIPIECE RIVET FOR FASTENING A PAIR OF WORKPIECES HAVING ALIGNED OPENINGS COMPRISING: A HOLLOW SLEEVE HAVING A SHANK PORTION ADAPTED TO PROJECT THROUGH THE ALIGNED OPENINGS AND BEYOND ONE SIDE OF THE WORKPIECES AND HAVING A PREFORMED HEAD ON ONE END OF SAID SHANK PORTION FOR ENGAGING THE OTHER SIDE OF THE WORKPIECES, SAID SLEEVE HAVING A THROUGH BORE TERMINATING IN A COUNTERBORE AT THE OTHER END OF SAID SHANK AND A RADIALLY OUTWARDLY FLARING CAVITY IN SAID HEAD, A SLEEVE STOP SHOULDER EXTENDING RADIALLY INWARDLY AT A POINT PROXIMATE TO THE TERMINATION OF SAID CAVITY AND DEFINING THE MINIMUM DIAMETER OPENING THROUGH SAID SLEEVE, A PIN, PULL MEANS FOR GRIPPING SAID PIN LOCATED AT ONE END OF SAID PIN, AN AXIALLY SPLINED PORTION LOCATED ADJACENT SAID PULL MEANS AND HAVING A MAXIMUM DIAMETER GREATER THAN THE DIAMETER OF SAID PULL MEANS BY SAID STOP SHOULDER OF SAID MINIMUM OPENING DEFINED BY SAID STOP SHOULDER OF SAID SLEEVE, A REDUCED DIAMETER PORTION LOCATED ADJACENT SAID SPLINED PORTION AND HAVING A DIAMETER LESS THAN SAID SPLINED PORTION AND LESS THAN SAID MINIMUM OPENING, AN ANNULAR BREAKNECK GROOVE LOCATED ADJACENT SAID REDUCED DIAMETER PORTION AND DEFINING THE WEAKEST SECTION OF SAID PIN, A LOCKING GROOVE LOCATED ADJACENT SAID BREAKNECK GROOVE AND HAVING A MAXIMUM DIAMETER LESS THAN SAID MINIMUM OPENING AND INCLUDING A PLURALITY OF ANNULAR LANDS SUCCESSIVELY DECREASING IN DIAMETER FROM A FIRST OF SAID LANDS AND FURTHER INCLUDING A LAST LAND HAVING A DIAMETER SUBSTANTIALLY EQUAL TO THE DIAMETER OF SAID FIRST LAND, A PIN STOP SHOULDER LOCATED ADJACENT SAID LAST LAND AND BEING OF A DIAMETER TO ENGAGE SAID SLEEVE STOP SHOULDER, A WIRE DRAWING PORTION LOCATED ADJACENT SAID PIN STOP SHOULDER AND INCLUDING A FIRST TAPERED PORTION TAPERING TO A SELECTED DIAMETER SLIGHTLY GREATER THAN THE DIAMETER OF SAID COUNTERBORE, A STRAIGHT, CYLINDRICAL BODY PORTION HAVING A DIAMETER OF SAID SELECTED DIAMETER, AND A REDUCED PORTION HAVING A DIAMETER GREATER THAN THAT OF SAID THROUGH BORE AND SLIGHTLY LESS THAN THAT OF SAID SELECTED DIAMETER, AND A HEAD PORTION TERMINATING THE OPPOSITE END OF SAID PIN AND HAVING A TAPERED PORTION TAPERING FROM A DIAMETER EQUAL TO THAT OF SAID REDUCED PORTION TO A DIAMETER SLIGHTLY GREATER THAN SAID SELECTED DIAMETER, SAID PIN HAVING A FIRST AXIAL LENGTH FROM SAID PIN STOP SHOULDER TO THE BEGINNING OF SAID HEAD PORTION BEING LESS THAN THAT FROM SAID SLEEVE STOP SHOULDER TO SAID OTHER END OF SAID SHANK SUCH THAT WITH SAID PIN AND SLEEVE STOP SHOULDERS ENGAGED SAID HEAD PORTION ENGAGES SAID OTHER END OF SAID SHANK AND SAID CAVITY IN SAID PREFORMED HEAD IS ALIGNED WITH SAID LOCKING GROOVE TO DEFINE A LOCKING CAVITY, A RADIALLY SPLIT, ANNULAR LOCKING RING HAVING AN INSIDE DIAMETER LESS THAN THE MAXIMUM DIAMETER OF SAID SPLINED PORTION AND BEING LOCATABLE ON SAID REDUCED DIAMETER PORTION AND BEING SWAGABLE IN SAID LOCKING CAVITY FOR ENGAGING THE SURFACES OF SAID CAVITY AND SAID PLURALITY OF LANDS FOR POSITIVELY LOCKING SAID PIN AND SAID SLEEVE TOGETHER.