Metallics JDWSR7C 8 x 2-1/2 in. Bugle Head Square Drive Drywall Screws - Steel Black Phosphate - Coarse Threads - Each

A #2 square drive bit. The recess is square, measuring 0.110 to 0.113 inch wide and 0.064 to 0.075 inch deep, so a #2 Robertson bit seats fully. A Phillips bit will not engage it.

No. Black phosphate is a mild corrosion coating for interior dry use, which is why the stated application is drywall and wood work indoors. For exterior decking, soffits, or anywhere exposed to moisture, choose a coated or galvanized deck screw instead.

No. These are not Buy American compliant and not ARRA compliant, with country of origin listed as multiple. On a federally funded job with domestic sourcing requirements, you will need a domestically manufactured fastener instead.

Bugle head is the profile made for that. The head is 0.315 to 0.363 inch across with a head height of 0.020 to 0.039 inch, so it countersinks itself into the board face and leaves a shallow dimple ready for compound. Set your drywall gun depth stop so the head sits just below the surface rather than driving past it.

They ship in a jar, 100 pieces minimum, weighing 0.95 lbs. Metallics notes other sizes and quantities can be supplied on request, so larger-volume packs for a full drywall hang are available through a request rather than off this size.

Within limits, yes. The thread is UNC coarse at 8 to 10 threads per inch with a sharp point, so it drives into softwood framing without pre-drilling and works for light wood-to-wood tasks like furring strips or blocking. They are not structural fasteners and they are not rated for ledgers, joist hangers, or outdoor framing.

The JDWSR7C is case hardened to Rockwell C45-64 and made from AISI 1018 steel, the standard hardness band for collated-style drywall screws. That hardness lets the sharp point bite wood without a pilot hole and keeps the square recess from deforming under a screw gun. Drive straight and on axis, as with any hardened screw, overdriving at an angle is what breaks heads.

Metallics states plainly that there is no single industry standard for drywall screw or bugle head dimensions, so the published head and recess figures are a guide and slight deviations are acceptable. If your spec calls out an exact head diameter or head height, treat the listed ranges (head width 0.315 to 0.363 in., head height 0.020 to 0.039 in.) as the band to compare against rather than fixed values.