Metallics TXV12114B 12-24 x 1-1/4 in. 5/16 Hex Head Heavy Duty Drill Screws - #5 Drill Point - All-Weather - Each

The TXV12114B is flagged both ARRA compliant and Buy American compliant, and the product description states it is made in the USA. That is the documentation a government, school district or federally funded project procurement file needs for a fastener line item.

Dimensions are to ASME B18.6.3-2010, threads to SAE J78-2013, and the steel is AISI 1016-1024. It is a Type BSD heavy duty drill screw, 12-24 thread with 24 threads per inch. Those are the three callouts an engineer or inspector asks for on a fastener submittal.

A 5/16 hex driver. The head is a hex type measuring 0.305 to 0.312 in. across the flats, 0.34 in. across the corners, with a head height of 0.139 to 0.155 in. There is no slotted or Phillips option, so a magnetic 5/16 hex nut setter in an impact or screw gun is the tool.

The TXV12114B carries a zinc plus All-Weather coating, which is why it's sold as an all-weather screw for exposed steel-to-steel work. The head finishes gray rather than bright zinc, so it blends with galvanized and painted steel better than a plain plated screw.

These are specified at 92 lb-in minimum torsional strength with a case hardness of Rockwell C32-40, so they are built to take gun-driven installation into structural steel. The usual failure on a job is overdriving past seating rather than the screw snapping, so set your clutch or depth-sensing nose piece and let the screw stop when the washer seats.

The head is an integral hex washer head, with a washer OD of 0.398 to 0.432 in. and a washer thickness of 0.022 to 0.039 in. No separate washer is needed for steel-to-steel fastening. If you are clamping a soft or oversized-hole material, add a bonded sealing washer yourself, since the integral washer is unsealed.

These ship as a box of 2500, which is the order minimum. Metallics notes that other sizes and quantities are available by request, so if you need a 100 or 500 count for a service truck rather than a full box, ask before ordering the 2500.

Type BSD is a heavy duty self-drilling screw: the point drills its own hole and the thread taps it in one pass, no pilot hole and no nut on the back side. On this 12-24 x 1-1/4 in. version with a #5 point, the application is steel-to-steel, things like hanging strut, mounting panels and brackets, or fastening to structural members and heavier gauge framing. If you can only reach one side of the steel, this is the fastener type for it.

A full box runs 31 lbs, in a carton measuring 9 x 9 x 6.13 in. Worth knowing if you are staging multiple boxes on a lift or spec'ing a material handling allowance on a multi-story steel job.