Metallics JTEKD32V 12 x 2 in. 5/16 Indented Hex Head Self-Drilling & Tapping Screws with Washer - #3 Drill Point - Steel Zinc - Each

Dimensions are to ASME B18.6.3-2010 and threads to SAE J78-2013, as a Type BSD self-drilling and tapping screw. Material is AISI 1016 to 1024 steel, case hardened to Rockwell C32-40, with minimum torsional strength of 92 lb-in. Note that SAE J78 does not cover #7 diameter drill screws, which is not an issue here since this is a #12.

Metallics lists the JTEKD32V as both Buy American compliant and ARRA compliant. Country of origin is reported as multiple, so if your contract requires a single named origin on the submittal, that is worth pinning down with your contract documents before you commit.

The washer is integral to the head, so nothing extra to buy. Washer outside diameter runs 0.398 to 0.432 inches with a thickness of 0.022 to 0.039 inches, which spreads the clamp load on thin sheet and helps seat flat without dimpling the panel.

Fastener length is 2 inches with a #12 diameter and 14 threads per inch, UNC. With a panel range of 0.110 to 0.210 inches, that 2 inch length leaves plenty of shank for stacking a bracket, clip, or wood blocking ahead of the steel. If you are only fastening sheet to sheet, a shorter screw is the better choice because excess point length sticking through the back can be a hazard.

They ship in a jar, with a minimum order of 500 count. Total package weight is 8.55 lbs. Metallics does make other sizes and quantities available by request if 500 of a 12 x 2 is more than the job needs.

The JTEKD32V is zinc plated carbon steel with a silver finish. Zinc plating is an indoor and sheltered-use coating, fine for dry interior steel framing, strut, and panel work. For sustained exterior exposure, washdown areas, or coastal sites, specify a stainless drill screw instead. Worth knowing: minimum torque figures are the same for stainless and steel self-drill screws, so switching to stainless does not cost you driving strength.

Metallics cites a drill time of 2.5 seconds through a 1 mm thick plate. Thicker material in the 0.110 to 0.210 inch range takes longer. Run them with a 5/16 inch hex driver at a controlled speed and let the point cut rather than leaning on the gun, since the screw is rated to 92 lb-in minimum torsional strength and over-driving is what snaps heads off.

Head height on the JTEKD32V runs 0.139 to 0.155 inches including the indented hex washer profile. That is a low-profile hex head, so it clears most cover plates and trim, but it is not a flush or countersunk fastener. If the surface has to be smooth, use a flat head screw instead.