Metallics JFWP120 4 x 1/2 in. Flat Head Phillips Wood Screws - Steel Zinc - Each

Yes, if the countersink is sized for a #4 head. The flat head on the JFWP120 measures 0.195 to 0.225 inch across with a head height of 0.067 inch, so a standard 82 degree countersink at that diameter brings it dead flush with the surface. Flat head is the right pick any time you are mounting a plate, strap, or cover that something else has to sit against.

No. The JFWP120 is not Buy American compliant and is not ARRA compliant, and the country of origin is listed as multiple. If you are on a federally funded project with domestic sourcing requirements, these will not satisfy it.

These come in a jar of 100, and 100 is the order minimum. That is the handy count for a van or a shop drawer rather than a bulk box, so if you are standardizing a whole building on one screw size you will want multiple jars.

Zinc plated steel, which is what the JFWP120 is, is a dry interior fastener. The plating gives light corrosion resistance for indoor work but it is not a marine or sustained-wet finish. For exterior trim, treated lumber, or anywhere it gets wet, move to a stainless or hot dip galvanized wood screw instead.

Essentially all of it. On short wood screws like this #4 x 1/2 inch, the threads run as close to the underside of the head as the manufacturing allows, because the nominal length is too short to fit the standard minimum thread length with a plain shank. Past 1 inch of length the pattern shifts to roughly two thirds thread. Practically: a 1/2 inch screw gives you about 1/2 inch of thread bite, so it is for thin stock and light attachments, not structural pull.

Yes. The JFWP120 is built to ASME B18.6.1, with threads to ASME B18.6.1-1997. That is the inch-series wood screw standard, so head diameter, head height, recess geometry and thread pitch are all to a published dimension rather than a house pattern. Useful if a submittal calls out a standard-conforming fastener.

Metallics lists these for the electrical, plumbing, and heating and air conditioning trades. In practice that means mounting small device plates, straps, clips, low voltage brackets, nameplates, and thermostat or sensor bases into wood framing or blocking. At 1/2 inch long with a #4 shank they are a light attachment screw, not a framing or hanging fastener.

Other sizes and quantities in the JFWP flat head Phillips wood screw line are available by request. The JFWP120 itself is the #4 x 1/2 inch in a 100 count jar, so if your opening needs more thread depth, ask for the longer length in the same series rather than substituting a different head style.