A fastener includes a shank having a first end and a second end defining a length. The fastener includes a thread provided on the shank, the thread including a first region adjacent to the first end and a second region between the first region and a head at the second end, the thread includes a leading edge and a trailing edge, each edge forming an angle with a surface of the shank, the leading edge forming a non-normal angle with the surface of the shank and the trailing edge forming an angle about normal to the surface of the shank. The fastener may include an arcuate detent region in the shank between respective turns of the thread, the detent region having a length, the length decreasing from the first end toward the second end between the respective turns. The fastener may include a plurality of flutes positioned along a length of the shank.

A thermal concrete wing nut anchor includes a screw having an external thread, and a wing nut mounted on the screw. The screw has a first end provided with an enlarged stop flange, and a second end provided with a drilling tip. The stop flange is provided with a driving head. The wing nut is made of a metal sheet plate which is formed integrally by pressing. The wing nut has a middle provided with a first ear and at least one second ear. The wing nut has an internal thread extending through the first ear and the at least one second ear. The external thread of the screw is screwed through the internal thread of the wing nut.

A screw includes a shank having a tip, a rear end which is disposed opposite the tip, and a longitudinal axis which extends through the tip and through the rear end. The shank consists of a first steel material. A screw thread helix is disposed on the shank and protrudes from the shank. The screw thread helix consists of a second steel material that is different from the first steel material. Both the first steel material and the second steel material are stainless steels.

A screw including a shank having a tip end and a rear end, which is located opposite the tip end, and at least one screw thread, which is arranged on the shank, which winds around the shank and which protrudes from the shank, wherein the screw thread includes a separate screw thread section, which is constituted by a separate helix element that is non-monolithically arranged on the shank. The at least one screw thread includes a thread start, which extends further towards the tip end than does the separate screw thread section, and which forms a generally helical continuation of the separate screw thread section, wherein the thread start and the shank are monolithic.

A drywall screw for fastening a plasterboard panel to a metal support is provided, the screw having a head, a tip portion and an elongate shank, wherein the tip portion adjoins the shank, wherein the drywall screw has a widening element for widening the first borehole in the plasterboard panel to a first borehole diameter t and breaking off upon impinging the metal support, wherein the head exceeds the first borehole diameter t with a pressing-in volume V.sub.1, wherein the shank has a thread-free underhead portion which falls below the first borehole diameter t with a receiving volume V.sub.2 which is at least 80% of the pressing-in volume V.sub.1.

A screw including a shank, wherein a thread helix receiving groove that winds around the shank is provided in the shank, and wherein the shank has a screw tip, and further including a thread helix having a base and a crest, wherein the thread helix and the shank are separate parts, wherein the base of the thread helix is arranged in the thread helix receiving groove, and wherein the crest of the thread helix projects radially from the shank. The crest of the thread helix of the unconstricted screw is displaceable towards the shank by linearly driving the shank, together with the thread helix, into an undersized borehole in a concrete or masonry substrate. A method for installing such a screw is also provided.

A screw and anchor assembly include a male fastener and a female anchor. The male fastener only has threads or half-circular fins on half of the surface area. The other half is just like a regular cylinder. The female anchor only has threads or half-circular fins on half of the inner surface area. The other half is just like the inner wall of a regular cylinder. The user may push the male fastener into the female anchor, so the half-circular fins on the male fastener engages with the half-circular fins inside the female anchor and locks the male fastener to the female anchor. When the user needs to remove the male fastener, simply turns the male fastener 180 degrees and disengages the half-circular fins on the male fastener from the half-circular fins on the female anchor, then pull the male fastener from the female anchor.

A screw includes a shank where a thread helix receiving groove winds around the shank and is disposed in the shank. A thread helix is disposed in the thread helix receiving groove where the thread helix has an expandable helix section. The shank has, at the thread helix receiving groove, a wedge flank for radially expanding the expandable helix section as the shank is moved relative to the expandable helix section. The expandable helix section has a helical back and a plurality of expansion fingers projecting axially from the helical back towards the wedge flank. The wedge flank of the thread helix receiving groove is configured for radially displacing the plurality of expansion fingers outwardly as the shank is moved relative to the plurality of expansion fingers.

A fastener includes a shank having a first end and a second end defining a length. The fastener includes a thread provided on the shank, the thread including a first region adjacent to the first end and a second region between the first region and a head at the second end, the thread includes a leading edge and a trailing edge, each edge forming an angle with a surface of the shank, the leading edge forming a non-normal angle with the surface of the shank and the trailing edge forming an angle about normal to the surface of the shank. The fastener may include an arcuate detent region in the shank between respective turns of the thread, the detent region having a length, the length decreasing from the first end toward the second end between the respective turns. The fastener may include a plurality of flutes positioned along a length of the shank.

A wall nail includes a rod body, a nail head, a rotary head, and a rubber cover. The rod body has a first end portion and a second end portion opposite to the first end portion. The nail head includes a threaded rod and a drill. Two ends of the threaded rod are integrally connected with the second end portion of the rod body and the drill respectively. The rotary head is integrally formed on the first end portion of the rod body. The rubber cover covers the peripheries of the rod body and the rotary head.