Metallics RSDS1B 8 x 1-1/4 in. Bugle Head Star Drive Deck Screws - Steel Yellow Zinc - Type 17 - Threads - Each

A T20 bit. The RSDS1B uses a star (flat six-lobe) recess, so a T20 star/Torx driver seats fully and resists cam-out. Keep spare T20 bits on the truck if you're running a full box, since a worn bit is what rounds out the recess on a long deck run.

No pre-drilling. The Type 17 point cuts a chip cavity ahead of the threads, so the screw drives without a pilot hole even in denser woods. That is what separates it from a plain-point wood screw, which will split a board end or stall in hardwood decking.

Yes. The bugle head on the RSDS1B pulls itself flush into wood as it seats, no countersink bit needed. The head measures 0.285 to 0.331 in. across and 0.108 in. tall, so it bears on a wide enough footprint to draw a board down without punching through softwood. On composite or capped decking, back off the trigger at the end of the drive, since a bugle head will keep sinking and mushroom the surface.

Treat yellow zinc dichromate as a dry or sheltered finish. The RSDS1B is plain carbon steel with a yellow zinc dichromate plating, and that coating is a light corrosion barrier, not a marine or ACQ-rated one. For an open exterior deck, pressure treated lumber, or anything near salt air, go to a stainless or a coated exterior deck screw instead. Under a roof, in a garage, on interior framing, or for temporary work, yellow zinc is fine.

They ship as a box of 2,580 screws, which is the order minimum. That is a jobsite quantity, roughly 15.74 lbs of fasteners, so it suits a contractor stocking a truck or an MRO crib rather than someone fastening a handful of boards. Metallics lists other sizes and quantities in the RSDS line by request.

Yes on both. The RSDS1B is flagged Buy American compliant and ARRA compliant, which is what a public-agency, school district, or federally funded project spec usually turns on. Country of origin is listed as multiple, so if your submittal requires a single named country of manufacture, confirm the origin on the specific lot you receive.

9 threads per inch, coarse UNC. That wide pitch is what makes it a wood and deck screw rather than a machine screw: fewer, deeper threads bite more wood fiber per turn, drive faster, and resist pull-out when a board wants to cup or lift. It also means it will not thread into a tapped metal hole, so do not substitute it for a machine screw in an enclosure or strut.

Star drive, for anything you are running by the hundred. The six-lobe recess on the RSDS1B takes a T20 bit and transmits torque with far less cam-out than a Phillips, which matters when the Type 17 point is boring its own hole in dense wood and the driver is loaded. Phillips deck screws chew out their recess and strand you with a half-driven screw you then have to extract. The tradeoff is that you need the right bit on hand; a T20 is not interchangeable with a square or Phillips driver.

AISI 1018 to 1022 low carbon steel, plated in yellow zinc dichromate. That is the standard case-hardenable range for driven wood fasteners: hard enough at the point to cut its own hole, ductile enough in the shank that the screw bends before it snaps when you hit a knot. It is not stainless, so the plating is the only corrosion protection it has.