Metallics TSP67B 14 x 21/4 in. Pan Head Phillips Sharp Point Tapping Screws - Steel Zinc - Each

It is a Type A tapping screw with a gimlet (sharp) point, so it forms its own thread as it drives into sheet metal, and it is not a drill point. In thin gauge metal it starts on its own; in heavier stock you still want a pilot hole. Threads are 10 per inch, UNC form, to ASME B18.6.4.

They ship as a box of 800 count, and 800 is the order minimum. No partial counts on this one, so plan the job around full boxes. The box runs 19.9 lbs.

Both the ARRA and Buy American compliance flags on the TSP67B are marked compliant. Country of origin is listed as multiple, so if your specifying authority wants a single named origin on the submittal, that is the detail to pin down before release.

A #3 Phillips bit. The recess on the TSP67B is 0.148 in deep with a 0.268 to 0.281 in diameter, so a #2 bit will cam out and chew the recess on a screw this size. Bring #3 bits if your crew is set up for #2 only.

Head width runs 0.457 to 0.476 in with a head height of 0.156 to 0.169 in, dimensioned to ASME B18.6.3-2013. That is just under a half inch of bearing surface, so it will bridge a slightly enlarged hole but not a knockout. If you need a wider footprint, put a washer under it.

The TSP67B is carbon steel with a zinc finish. Zinc plating handles indoor and sheltered conditions fine, which is what the screw is built for (electrical, plumbing, heating and air conditioning work). For direct weather exposure or wet locations, specify stainless instead.

A Type A screw like the TSP67B has a gimlet point that pierces and forms a thread in thin sheet metal, but it has no cutting flutes, so it will not bore through heavy steel. A self-drilling screw carries a drill tip and cuts its own hole in thicker stock. For sheet metal enclosures, strut, and light gauge hangers, the Type A is the normal pick; for structural or heavy gauge steel, go self-drilling.