Product Description These sheet metal screws, or tapping screws, are highly versatile and are used to attached metal, wood, fiberglass, and plastic. The sharp threads draw material together and ensure a secure hold. Sheet metal screws are fully threaded with a sharp point. . From the Manufacturer These sheet metal screws, or tapping screws, are highly versatile and are used to attached metal, wood, fiberglass, and plastic. The sharp threads draw material together and ensure a secure hold. Sheet metal screws are fully threaded with a sharp point.