Metallics TXV143 1/4-20 x 3 in. 5/16 Hex Head Heavy Duty Drill Screws - #5 Drill Point - All-Weather - Each

The TXV143 carries a #5 drill point, which is the heavy end of the self-drilling range and is intended for steel-to-steel work rather than light gauge sheet. Metallics lists it as a Type BSD Heavy Duty Drill Screw for heavy duty steel-to-steel application, so it is the screw you reach for on structural steel, bar joist, and heavy channel where a #2 or #3 point would burn up before it cut through.

Yes. The TXV143 is supplied with a zinc/all-weather coating, which is what the All-Weather designation in the name refers to. That makes it suitable for exterior strut, rooftop equipment supports, and other work exposed to weather, as opposed to a plain zinc screw meant for dry interior use.

No. The TXV143 is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. If your contract carries a domestic sourcing clause, this is not the fastener for that scope.

A 5/16 hex driver or nut setter. The TXV143 has a hex head with hex drive, so it drives with a socket rather than a bit tip, which is what lets you put the torque into it that a #5 point needs. Torsional strength is rated at 150 lb-in minimum.

Yes. The TXV143 is a 1/4-20 machine thread, 20 threads per inch, made to SAE J78 - 2013, so standard 1/4-20 nuts and tapped hardware thread onto it. Overall length is 3 inches.

There is an integral washer under the head, measuring 0.480 to 0.520 inches outside diameter and 0.030 to 0.050 inches thick. That spreads the clamp load on strut, clip, and bracket connections, so you do not need to stack a separate flat washer under the head for a normal steel-to-steel fastening.

At 3 inches the TXV143 is sized for stacked connections, thick flange steel, or fastening through insulation, sheathing, or a double layer of strut into structure. For a single strut channel flat against a beam flange, a shorter TXV screw makes more sense, since excess unthreaded shank does nothing for holding power. Metallics makes other lengths in the TXV series available by request.

The TXV143 is made from AISI 1016 - 1024 carbon steel and case hardened to Rockwell C32-40, which is what lets the drill point cut structural steel without rolling over. Dimensionally it is made to ASME B18.6.3-2010.

They ship in a jar, with a minimum order quantity of 100 count. If you need a different length or a larger quantity in the TXV series, Metallics states other sizes and quantities are available by request.