Metallics TXV144 1/4-20 x 4 in. 5/16 Hex Head Heavy Duty Drill Screws - #5 Drill Point - All-Weather - Each

The Metallics TXV144 carries a #5 drill point, which is the heaviest point class Metallics puts on this Type BSD screw and is intended for heavy steel-to-steel work rather than light gauge sheet. It needs no pilot hole, and with 20 threads per inch on a 1/4-20 shank it taps its own thread as it goes. If you are fastening thin gauge decking or light studs, a smaller drill point screw is the better match.

The TXV144 is rated to a minimum torsional strength of 150 lb-in and is case hardened to Rockwell C32-40, made from AISI 1016-1024 carbon steel. Those are the numbers that govern whether the screw twists off before it finishes drilling. Even so, drive it at a controlled speed with steady pressure; an impact run flat out will overheat the point on thick steel.

No. The TXV144 is listed as not Buy American compliant and not ARRA compliant, with a multiple country of origin. If your project carries a domestic sourcing clause, this is not the screw to spec for it.

A 5/16 inch hex driver or socket. The head measures 0.367 to 0.375 inch across the flats and 0.409 inch across the corners, with a head height of 0.172 to 0.19 inch. It is an external hex drive, so a magnetic nutsetter in an impact driver or screw gun is the normal tool, not a bit.

Yes. The TXV144 is finished with a zinc/all-weather coating, which is what the "all-weather" designation on these Metallics screws refers to. That makes it suitable for exterior and damp-location steel-to-steel fastening, such as rooftop equipment supports, strut, and exposed framing.

The head is a washer head with an outside diameter of 0.480 to 0.520 inch and a washer thickness of 0.030 to 0.050 inch. That spreads the clamp load across the hole, which matters when you are drilling through slotted strut or oversized holes. The washer is integral to the head, so there is no separate part to order.

The order minimum on the TXV144 is 50 each, supplied in a jar. The 4 inch length and 1/4-20 diameter is one size in the Metallics TXV series, and Metallics notes that other sizes and quantities are available by request.

Threads are to SAE J78-2013, the standard for steel self-drilling tapping screws, and the head and overall dimensions follow ASME B18.6.3-2010. If a drawing calls out a self-drilling screw to SAE J78, the TXV144 answers that call at 1/4-20 by 4 inches.

At 4 inches of total length, the TXV144 gives you a long unthreaded reach before the drill point and thread engage the far layer, which is why this length gets used to pass through a spacer, sleeper, or insulation board and still bite structural steel underneath. Add up your layer thicknesses plus at least three threads of engagement in the base steel; if that total exceeds 4 inches, you need a longer screw or a through-bolt instead.