Anchors are inserts, typically made from plastic, metal, or fiber, which enable the attachment of screws into brittle materials — such as masonry or dry wall.
Known as wall plugs in the UK, anchors are available in many forms and offer anchoring solutions for different substrates at varying levels of strength.
Twisted Type Foundation Anchor
Drop In Anchor
A square nut is a four-sided nut. Compared to standard hex nuts, square nuts have a greater surface in contact with the part being fastened, and therefore provide greater resistance to loosening