Metallics DWSR3M 6 x 1-1/4 in. Bugle Head Square Drywall Screws - Steel Black Phosphate - Coarse Threads - Each

A #1 square (Robertson) bit. The recess is square drive sized for a #1 driver, measuring 0.090 to 0.106 in. wide and 0.055 to 0.071 in. deep. A #2 square bit will not seat in it. Square drive is worth having on a drywall job because the bit holds the screw without a magnet and cams out far less than Phillips when you are driving overhead.

No. Black phosphate is a dry interior finish with minimal corrosion resistance, and these Metallics screws are steel with a black phosphate coating. Use them for interior drywall over wood. For exterior work, a wet area, or anything in contact with treated lumber, go to a coated exterior or deck screw.

No. The DWSR3M is not Buy American compliant and not ARRA compliant, and country of origin is multiple. If your project carries a domestic sourcing requirement, these will not satisfy it.

These ship in a jar with a 1,000 piece minimum, so one order unit is 1,000 screws weighing 3.67 lbs. There is no smaller break on the DWSR3M.

That is what the bugle profile is for. The DWSR3M has a bugle head 0.315 to 0.347 in. across with a head height of only 0.020 to 0.031 in., so the curved underside compresses the paper and seats just below the surface rather than cutting it. Set your screw gun depth so the head dimples the board; driving past that still breaks the face regardless of head shape.

AISI 1018 steel, case hardened to Rockwell C45-64. That hardness is what lets the sharp point start in wood and the #1 square recess take torque from a screw gun without stripping. It also means the shank is brittle rather than ductile, so these are not a structural or shear fastener, just a drywall-to-wood screw.

There isn't one. Metallics publishes the DWSR3M dimensions as a guide and notes that slight deviations are acceptable, because no single industry standard governs drywall screw or bugle head dimensions. Practically, that is why head width shows as a range (0.315 to 0.347 in.) and thread count as 8 to 10 per inch with UNC coarse thread. If you are matching a submittal that calls out exact head diameter, expect tolerance rather than a fixed number.

Within reason. The field application for the DWSR3M is drywall and wood, and the coarse UNC thread with a sharp point will pull into softwood furring fine. The bugle head is shallow (0.020 to 0.031 in. high) and sized for gypsum, so in solid wood it tends to sit proud unless you countersink. For finish trim a trim head screw or finish nail gives a cleaner result.