Lead machine screw anchors work well for installations in old concrete where crumbling poses an issue. They’re also an excellent choice when working with brick or block materials. Machine screw anchors come preassembled and include an expansion cone insert and specially designed lead-alloy caulking sleeve. The cone expands and fills the hole, while the lead alloy molds to the surface and forms a secure fit that will hold up well in most environments.
Lead screw anchors can accommodate just about any head-style screw and adapt easily to multiple hole-size variations. They also have strong holding power, and their short length makes them an ideal choice for use in shallow holes, as well as with cap screws and other forms of machine-screw-threaded fasteners. You can also tighten, loosen or remove this screw as needed.