Patent ID: 8652183

Claim:
An expansion fastener having a removable locking ring, a head, and a shaft extending from a distal end of said head, said locking ring having an outer periphery, at least one tab, said at least one tab extending beyond said outer periphery and a tool receiving area, said head being substantially cylindrical and having: a proximal end, said proximal end having a first exterior diameter and an open area, said open area having a periphery, an edge, and a base, a middle section, said middle section having a tool receiving area contiguous with said open area of said proximal end and a second exterior diameter, said second exterior diameter being greater than said first exterior diameter, a distal end, said distal end having a tool receiving area and a third exterior diameter, said third exterior diameter being less than said first exterior diameter and said second exterior diameter, a channel along the periphery of said open area between a top rim and said base, said periphery forming a channel wall, said top rim interior diameter being dimensioned to receive said outer periphery of said locking ring, at least one tab receiving area within said top rim, each of said at least one tab receiving area being dimensioned to receive said at least one tab, said channel distal said at least one tab receiving area being dimensioned to receive said at least one tab, at least one wall periphery reduction along said channel wall adjacent to each of said at least one receiving area and, said periphery reduction being gradual from a minimum reduction end to a maximum reduction end, adjacent to said at least one receiving area, to control expansion adjacent to each of the tab receiving areas, at least one slot, said at least one slot extending from said edge of said head toward said distal end, wherein rotation of said locking ring from said receiving area along said wall periphery reduction gradually expands the outer diameter of said head at each of said at least one slot from minimum diameter up to a maximum diameter.