In one embodiment, a fastener includes a flexible head and a shank coupled to the flexible head. The flexible head includes a center head portion and a plurality of wing portions coupled to the center head portion. Each of the plurality of wing portions includes a contact area configured to contact a first surface of a part to be fastened. The shank includes a clip groove configured to hold a retainer clip against a second surface of the part to be fastened. The second first surface of the part to be fastened is opposite the first surface of the part to be fastened.

A threaded fastener assembly for use with a nut includes a shaft head and a separate shaft. The shaft head includes a head, and an internally-threaded portion. The shaft has a first externally-threaded portion for cooperation with the internally-threaded portion of the shaft head to selectively secure the shaft to the shaft head, a second externally-threaded portion for cooperation with the nut, and an integrated nut or wrenching portion for tightening the shaft to the shaft head.

A fastener system incorporated in a structural member, the system including a dual threaded member and an anti-rotational member. The dual threaded member is inserted through a hole in the structural member. The dual threaded member has an engaging feature. The anti-rotational member is coupled to the dual threaded member, and the anti-rotational member is coupled with the engaging feature of the dual threaded member and with the structural member to thereby limit rotation of the dual threaded member relative to the structural member.

A fastener including a pin member having a shank portion, a threaded portion having a thread, a lock portion having at least one lock groove, and a pull portion located having at least one pull groove. The threaded portion is adapted to be engaged threadedly with a threaded hole of a workpiece to install the pin member therein. The fastener includes a swage collar adapted to be installed into the at least one lock groove of the lock portion to secure a plurality of workpieces. The pull portion is adapted to break off when the fastener is installed.

A fastener including a pin member having a shank portion, a threaded portion having a thread, a lock portion having at least one lock groove, and a pull portion located having at least one pull groove. The threaded portion is adapted to be engaged threadedly with a threaded hole of a workpiece to install the pin member therein. The fastener includes a swage collar adapted to be installed into the at least one lock groove of the lock portion to secure a plurality of workpieces. The pull portion is adapted to break off when the fastener is installed.

A removable fastener for securing a first stud to a second stud each stud having an aperture with lateral and bottom edges, includes a joining member with a first end and second end having first and second notches sized to admit lateral edges made adjacent by placing the studs back-to-back. Fastener includes a locking member that has a stud end configured to rest on the bottom edges of the apertures and a fastener end configured to attach to the joining member, holding the joining member in position within the apertures when the joining member is engaged within the apertures; the fastener end may include a clip.

A removable fastener for securing a first stud to a second stud each stud having an aperture with lateral and bottom edges, includes a joining member with a first end and second end having first and second notches sized to admit lateral edges made adjacent by placing the studs back-to-back. Fastener includes a locking member that has a stud end configured to rest on the bottom edges of the apertures and a fastener end configured to attach to the joining member, holding the joining member in position within the apertures when the joining member is engaged within the apertures; the fastener end may include a clip.

Aspects herein are generally directed to a fastener having a disco-rectangular cross-sectional shape. This shape is advantageous for purposes of gripping and as the disco-rectangular shape provides a gap between the edges of a countersunk bore and the edges of the disco-rectangular shape. As such, a user of the disco-rectangular shape may be able to grip the edges of the disco-rectangular shape, with fingers or any other type of tool.

A rolled thread screw includes: a screw part having, on an outer circumferential part of the screw part, thread crests and thread grooves disposed alternately along an axial direction of the rolled thread screw; and a columnar part adjoining at least one of both sides of the screw part in the axial direction. An axial end surface of the columnar part is provided with: a first concave surface concave in the axial direction; a second concave surface positioned to an outer circumference of the first concave surface and being concave in the axial direction; and a salient part positioned on a boundary between the first concave surface and the second concave surface and projecting further than a bottom of the first concave surface and a bottom of the second concave surface, the salient part extending in an arc-like shape along a circumferential direction of the columnar part as viewed in the axial direction.

A fastener including a pin member having a shank portion, a threaded portion having a thread, a lock portion having at least one lock groove, and a pull portion located having at least one pull groove. The threaded portion is adapted to be engaged threadedly with a threaded hole of a workpiece to install the pin member therein. The fastener includes a swage collar adapted to be installed into the at least one lock groove of the lock portion to secure a plurality of workpieces. The pull portion is adapted to break off when the fastener is installed.