These screws are used to cut or form a mating thread when driven into preformed holes. They permit rapid installation, since nuts are not used and access is required from only one side of the joint.

Self-tapping screws are usually drilled into pre-made holes (pilot holes) in metals, such as zinc, aluminum, and bronze and its alloys, as well as plastics and resin-impregnated plywood. They create ...

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