Molly (fastener)

The molly bolt was patented in 1934 by George Frederick Croessant. Although his patent acknowledges that expandable fasteners of this general kind were already known, Croessant's patent is intended to provide "an improved and adequate anchoring grip that may be retightened if necessary and that will permit repeated withdrawals and reengagements of the associated bolt." The same year, Croessant also registered the trademark "MOLLY". ==Attaching==

The fastener is an anchor, an expandable sleeve that slides into a hole drilled into the wall. A lip wider than the hole prevents it from falling behind the wall, and often features such as cleats/spikes prevent it from rotating when being compressed. A machine screw is screwed into the sleeve, causing the anchor to bend, expand, spread and grip against the inside of the hole or behind it (in hollow contexts such as drywall over stud cavities, or hollow doors). Mollies come in various diameters and grip lengths (shank lengths) for different drywall thicknesses and to support different loads. ==See also==