Ultra TEK Screws Length : 40mm 250 Pcs Per Box Tek screws, which are self-tapping fasteners, have a very small carving at the end of its tip called a drill bit. This particular product is very popular since it is basically a self drilling product cutting back on the number of steps necessary to complete projects by eliminating the need to pre-drill.hese screws are meant for metal to metal applications only with the exception of the reamer tek screw which is designed exclusively for a WOOD to METAL application. These screws come in varying sizes. In the case of hex head tek screws, check our our video to help you understand how to determine the size of screws based simply on the size of the hex head plus other additional information. Self-drilling screws, tek screws, are available in a variety of shank diameters and lengths as well as head styles. Depending upon the type of work you are using them will dictate which type you need to complete your project. More informayion about rigid insulation.
