Metallics RSDS3B 8 x 1-3/4 in. Bugle Head Star Drive Deck Screws - Steel Yellow Zinc - Type 17 - Threads - Each

A T20 star bit. The RSDS3B uses a flat six-lobe star drive, so a T20 Torx-style driver seats fully and won't cam out the way a Phillips does when you're running screws all day off a impact driver.

No. The RSDS3B carries a Type 17 point, the chip cavity or auger point that lets the fastener drive even in denser woods without pre-drilling a pilot hole. That is the whole reason to reach for a Type 17 on decking and framing work instead of a plain sharp-point screw.

At 1-3/4 inches overall length, the RSDS3B is sized for nominal 1-inch decking or 3/4-inch sheet material into a joist, leaving roughly an inch of thread in the framing member. For full 2x decking you want a longer screw; this one won't reach enough substrate.

Treat the yellow zinc dichromate finish on the RSDS3B as a corrosion coating for general construction and covered or interior work, not as a stainless or ceramic-coated exterior fastener. Modern ACQ-type pressure treated lumber is aggressive on plain zinc plating. For exposed decking in treated lumber or anywhere near salt air, specify a coated or stainless deck screw instead.

Yes, that's what the bugle head does. The head on the RSDS3B measures 0.285 to 0.331 inch across and 0.108 inch high, and the flared bugle profile pulls itself into softwood so the top of the head finishes flush with the board face. No separate countersink step.

They ship as a box with a 1,875-piece minimum, so this is a jobsite or shop quantity rather than a handful. The full box runs 15.56 lbs and the carton measures 11.5 x 10.75 x 11.5 inches, which matters if you're staging material on a shelf or in a van bin.

The RSDS3B is flagged compliant for both Buy American and ARRA, which is what a public-sector or federally funded spec typically asks for on fasteners. Country of origin is listed as multiple, so if your contract requires a single named country of manufacture on the submittal, confirm the origin on the lot you receive.

For mounting blocking, plywood backer boards, and panel backing, the RSDS3B is the better choice of the two. Drywall screws are brittle bugle-head fasteners meant only to hold board to stud. This one is a coarse 9 TPI UNC screw in 1018-1022 steel with a Type 17 point that drives without a pilot, so it holds structurally in wood where a drywall screw would shear. It is not a substitute for a rated structural or lag screw where the drawing calls one out.

AISI 1018 to 1022 low-carbon steel, which is the standard run for hardened construction screws. Combined with the deeper thread form and the Type 17 auger point clearing chips ahead of the shank, the RSDS3B drives into denser woods without the torque spike that shears heads. Back the speed down in true hardwoods and let the point do the cutting.

Nine threads per inch in a UNC coarse form. That coarse spacing is what you want in wood and composite framing, it bites more fiber per turn and holds against pull-out. It also means these are not interchangeable with a fine-thread screw meant for metal studs or steel track.