Hanger bolt
A hanger bolt is a fastening screw that has a wood or dowel thread at one end and a (metric) thread at the other . You can z. B. used to attach an object with a nut to wood , masonry , natural stone or concrete . A classic example is the wall mounting of a washbasin or a wall-mounted element in the bathroom. One advantage is that when assembling the object, the screw axis only needs to be accessible from the side in order to set the nut (possible in a narrow space). Another advantage is the quick dismantling (and reassembly) via the short metric thread without unscrewing the dowel screw connection and thereby becoming worn and weakened.
Hanger bolts have a hexagon between the threads so that they can be screwed into the wall with an open-end wrench . There are also versions in which the hexagon sits at the end, or which also have an Allen or Torx drive . If these types of drive fail, the hanger bolt can also be turned with the help of locked nuts.