Metallics DWSR4M 6 x 15/8 in. Bugle Head Square Drywall Screws - Steel Black Phosphate - Coarse Threads - Each

A #1 square drive bit. The recess is square, 0.090 to 0.106 inch wide and 0.055 to 0.071 inch deep, so a #1 Robertson bit seats fully. A #2 square bit will cam out or sit proud. Worth buying spare bits if you're running the full jar.

No. Black phosphate is a dry interior finish only, it offers very little corrosion resistance and will bleed rust through paint or compound if it gets wet. The DWSR4M is a steel black phosphate screw meant for interior drywall over wood. For exterior sheathing, soffits, or wet areas use a coated or stainless deck screw instead.

The bugle head has a curved underside that compresses the paper face and seats flush without tearing it, so the dimple takes joint compound cleanly. Head width on the DWSR4M runs 0.315 to 0.347 inch with a head height of 0.020 to 0.031 inch, which is why it sinks nearly level with the board. A flat or pan head would either cut the paper or stand proud and telegraph through the finish.

They ship in a jar, 1000 pieces, and 1000 is the order minimum. Figure one jar covers a few hundred square feet of board at typical screw spacing, so order by the jar count your job needs rather than loose counts.

No. The DWSR4M is listed as not Buy American compliant and not ARRA compliant, with multiple countries of origin. If your contract carries a domestic sourcing clause, this screw won't clear it and you'll need a domestically produced fastener.

The DWSR4M is case hardened to Rockwell C45-64 on AISI 1018 steel, which is the standard range for drywall screws. That hardness lets the sharp point bite without the tip rolling over. Snapped heads usually come from overdriving with too much clutch or torque rather than the screw itself, so set a drywall depth stop on the gun.

Close, but not identical. There is no single industry standard for drywall screw or bugle head dimensions, so Metallics publishes the head width (0.315 to 0.347 inch), head height (0.020 to 0.031 inch), and thread count (8 to 10 per inch) as ranges and slight deviations are normal. In practice any #6 coarse bugle head screw mixes fine on the same wall, but keep one brand per job if you're fussy about the dimple depth your gun is set for.