Metallics JTSP16 8 x 1/4 in. Pan Head Phillips Sharp Point Tapping Screws - Steel Zinc - Each

The Metallics JTSP16 is a #8 x 1/4 inch Type A tapping screw with a gimlet (sharp) point. The sharp point and coarse 15 threads per inch let it form its own thread in sheet metal, electrical boxes, panel enclosures and similar thin material without a pre-tapped hole. It is not a machine screw, so it will not thread into an existing 8-32 tapped hole.

At 1/4 inch overall length under a pan head, the JTSP16 gives you roughly a quarter inch of usable thread, so it is meant for sheet steel and thin stock - box covers, straps, clips, mounting plates. If you are fastening through a spacer, a wood substrate, or anything stacked, step up to a longer length in the same JTSP series; this one will bottom out before it pulls tight.

The head measures 0.306 to 0.322 inch across and 0.105 to 0.115 inch high. That is a flat-bearing pan head that sits on top of the material, not a flush head. If your part is countersunk for a flat head, these will stand proud and rock. Check your clearance hole is smaller than about 0.306 inch or the head will pull through.

A #2 Phillips. The recess is a Phillips drive measuring 0.169 to 0.182 inch in diameter, 0.108 inch deep, with a 0.03 inch recess width, so a #2 bit seats fully. A #1 will cam out and chew the recess.

The finish is zinc plating over carbon steel. That is an indoor, dry-location coating - fine for panel interiors, junction boxes and conditioned spaces. For exterior, wet, or corrosive environments you want stainless or a hot-dip galvanized fastener instead; zinc plate will rust through in those conditions.

Metallics lists the JTSP16 as both ARRA compliant and Buy American compliant, with country of origin China. If your specification requires domestic melt and manufacture rather than the ARRA/Buy American designation the manufacturer carries, verify against your project's exact clause language.

Two apply: head and drive dimensions follow ASME B18.6.3-2013, and the thread form follows ASME B18.6.4. Material is AISI 1016 to 1024 steel. One caveat the manufacturer notes - dimensions for #9 diameter screws in the series sit outside ASME B18.6.4; the #8 diameter JTSP16 is not affected.

Not interchangeably. The JTSP16 has a gimlet point, which pierces thin sheet or starts in a pilot hole. A self-drilling (Type TEK) point has a drill flute and is built for heavier gauge steel where a sharp point will just spin. For thin box steel and covers the sharp point drives faster and with less torque; for structural or thicker gauge, go self-drilling.

They come in a jar of 100, and 100 count is the order minimum. Handy for a van stock item or a shop bin rather than buying a bulk box you will not get through.