Metallics JTSP43 8 x 3 in. Pan Head Phillips Sharp Point Tapping Screws - Steel Zinc - Each

The JTSP43 is a #8 x 3 inch Type A tapping screw with a gimlet (sharp) point. Type A threads are coarse, 15 threads per inch here, and the sharp point is made for thin sheet metal, wood, and fiber materials where the screw forms its own thread as it drives. It is not a self-drilling screw, so thicker steel needs a pilot hole.

A #2 Phillips bit. The recess is a Phillips drive sized 0.169 to 0.182 inch in diameter and 0.108 inch deep, which is standard #2 territory, so one bit covers the whole jar.

The pan head measures 0.306 to 0.322 inch across and 0.105 to 0.115 inch high, so it sits roughly an eighth of an inch proud with a broad bearing surface. That is a surface-mount head, not a flush one. If you need the fastener to sit flat in a countersunk hole, a pan head is the wrong profile.

Zinc plating on carbon steel is an indoor and protected-location finish. It handles dry interior work and occasional moisture, but in direct weather, wet locations, or coastal exposure it will corrode. For exterior or damp duty, step up to a stainless or hot dip galvanized fastener instead.

They ship in a jar of 100, which is the order minimum, with the jar weighing 1.41 lbs. Handy for a van or a shop drawer rather than loose counts off a bin.

The JTSP43 is flagged compliant for both Buy American and ARRA, with country of origin China. On federally funded work, confirm which clause your contract actually cites, since Buy American Act and BABA thresholds are not identical.

Head and recess dimensions follow ASME B18.6.3-2013; the thread form follows ASME B18.6.4, the tapping screw standard. So a submittal calling for a B18.6.4 Type A tapping screw with a B18.6.3 pan head is satisfied. Note that #9 diameter dimensions in the Metallics range fall outside B18.6.4 - the #8 covered here does not.

For a straight sheet metal to sheet metal connection, 3 inches is far more screw than the joint needs and the extra shank just hangs in the cavity. The #8 x 3 inch sharp point Type A makes sense when you are going through a thick layer, a strap, blocking, or a wood member and into sheet metal or wood underneath. For attaching directly to a steel stud, a short self-drilling screw is the better fastener.