Metallics JPMP120 4-40 x 2 in. Pan Head Phillips Machine Screws - Steel Zinc - Each

4-40 is a machine screw thread with 40 threads per inch, cut to mate with a tapped 4-40 hole or a 4-40 nut. It is not the 6-32 thread used on most wiring device and wall plate mounting ears, so it will not thread into a standard receptacle or switch strap. Use it where the equipment is actually tapped 4-40, such as small enclosures, panel-mounted components, and terminal blocks.

They're carbon steel with a zinc plating, which handles dry interior and normally damp service but is not a corrosion-resistant fastener. For wet locations, exterior enclosures, coastal sites, or anywhere washdown is involved, specify a stainless 4-40 instead. Zinc plating on steel will eventually bloom white rust and then red.

A #1 Phillips driver. The recess on these 4-40 pan head screws is 0.115 inch in diameter with a gaging depth of 0.053 to 0.071 inch, so a #2 bit will cam out and chew the recess on a small head like this. Keep a #1 in the pouch if you're running these.

The threaded length is a full 2 inches, which is long for a 4-40 and is what you buy it for: reaching through spacers, standoffs, gasket stacks, or a deep enclosure flange into a nut on the far side. Head height runs 0.07 to 0.08 inch and head width 0.205 to 0.219 inch, so the head sits nearly flush and clears tight recesses.

Dimensions conform to ASME B18.6.3-2010, the standard for machine screws, and the material is AISI 1006 to 1022 low carbon steel. Tensile strength is 60,000 psi minimum with hardness Rockwell B70 to B100. That is the set of values an inspector or a submittal reviewer normally asks for on a machine screw.

Metallics lists the JPMP120 as both ARRA compliant and Buy American compliant, with country of origin recorded as multiple. If your spec demands a single named origin on the certification, confirm the lot origin with the order rather than relying on the multi-origin listing.

Pan head is the general purpose choice: a rounded top with a flat bearing face that seats on the surface, so it works in a plain drilled or tapped through-hole with no countersink. If the part has a countersunk hole or the head has to sit flush with the surface, you want a flat head machine screw instead, not this one. Head width here is 0.205 to 0.219 inch, so the bearing area is small, use a washer on soft or oversized holes.

No. The jar contains the 4-40 x 2 inch pan head Phillips screws only. If the hole you are fastening into is not already tapped 4-40, order 4-40 machine screw nuts and any flat washers or lock washers separately.

They come in a jar of 100, and 100 count is the order minimum. Shop-friendly packaging if you're stocking a van or a parts bin rather than buying a bulk box.