Metallics RSDS1V 8 x 1-1/4 in. Bugle Head Star Drive Deck Screws - Steel Yellow Zinc - Type 17 - Threads - Each

A T20 star bit. The RSDS1V uses a flat six-lobe (star) recess, so a T20 Torx-style driver seats fully and lets you run the screw at high torque without camming out the way a Phillips does on decking work.

No. The RSDS1V carries a Type 17 point, the auger-style chip cavity at the tip that clears material as it drives, so it goes into denser woods without a pilot hole. Near a board end or edge, or in hardwood trim where splitting is a real risk, a pilot is still the safer call.

Yellow zinc dichromate is a sacrificial plating meant for dry or sheltered service, not sustained weather exposure. On an open exterior deck, or in contact with modern ACQ/copper-azole pressure-treated lumber, the plating gives up quickly and the fastener corrodes. Use the RSDS1V for interior framing, subfloor, panel, and sheltered work; for wet exterior or treated-wood contact, specify a coated or stainless deck screw instead.

Bugle heads self-countersink in wood, so no separate countersink step. The head measures 0.285 to 0.331 inches across and 0.108 inches high, and the curved underside pulls itself down into the fiber and seats flush or slightly below. In a hard composite or a metal panel it won't self-sink cleanly, so counterbore first.

They ship in a jar with a 500-count minimum order. That's the buy quantity for the RSDS1V, so an order is placed in jars of 500 rather than by the piece. Total weight is 3.05 lbs.

Metallics lists the RSDS1V as compliant for both ARRA and Buy American, which is what a government, education, or healthcare procurement file needs on a federally funded job. Country of origin is listed as multiple.

Nine threads per inch, a coarse UNC pitch with the deep thread form Metallics specifies for pull-out resistance. Coarse and deep is what you want in softwood framing, plywood, and composites, where a fine thread strips out. In steel or a machine-threaded hole, this is the wrong fastener entirely.

AISI 1018 to 1022 low-carbon steel, plated in yellow zinc dichromate. That's a case-hardenable carbon steel, which is what lets the Type 17 point cut its own hole. It also means the screw is not stainless and shouldn't be mixed into a stainless assembly where galvanic corrosion matters.

The RSDS family is a star-drive deck screw series, and the RSDS1V at #8 x 1-1/4 in. takes a T20. Adjacent diameters in the series can call for a different bit size, so match the driver to the specific model rather than assuming one bit runs the whole range. For a crew working only this size, a handful of T20 bits covers the job.