GRK 16077#8 x 2" RT Composite Exterior Trim Screws 725 Count

Why I keep a box of these in the truck

I reached for the RT Composite trim screws on a Trex-clad stair rebuild and a PVC fascia refresh, and they’ve been living in my kit ever since. At #8 x 2", they hit a sweet spot for decking skins, cellular PVC trim, and a lot of interior detail work where a small, clean head matters. They’re not flashy; they just drive straight, hold tight, and leave a tidy surface—exactly what I want from a specialty fastener.

Design and features that matter on site

• Trim head profile: The small head disappears nicely in composite and PVC without leaving a crater. It’s far less obtrusive than a standard bugle head, and I’ve been able to keep fastener lines visible but subtle on deck stairs and skirt boards.

• Underhead reverse thread: This is the standout. On composites that love to “mushroom,” the reverse thread under the head helps shave down and seat the material instead of piling it up around the head. On softer PVC, it also pulls joints tight without tearing out the face.

• Torx drive (T-10): The head uses a T-10 star drive. Engagement is positive, and cam-out is rare if you keep the bit seated. My box included a single bit; I bring extras because T-10 bits wear faster than T-15 under an impact driver.

• Exterior-rated coating: The gold finish has held up well in my mixed-climate installs. After months of exposure on a north-facing stair run, I haven’t seen rust blooms or staining.

Driving and holding performance

I drove a few hundred of these into Trex treads and risers over pressure-treated stringers. In most locations, I could run them without pre-drilling, set the clutch right, and end up with a snug, nearly flush head. On denser boards or colder mornings when composite gets cranky, a small pilot hole pays off—especially if you want the head dead flush with zero witness. For PVC trim, pre-drilling near edges keeps things crisp and prevents wandering.

The screws bite quickly, track straight, and don’t snap under a sensible impact setting. Head stripping wasn’t an issue, but with T-10 you have to be deliberate: keep the bit square, lean in, and don’t freehand with a loose wrist. I set my impact to a lower torque for the last few threads to avoid overdriving; the trim head will countersink itself a touch, but you can dish out soft materials if you overdo it.

Holding power is exactly what it should be for a #8 trim screw. Into seasoned framing or PT, the grip is secure and repeatable. On stair treads, I didn’t have any fasteners back out after seasonal movement. On PVC returns and corner boards, the underhead reverse thread helped pull miters tight. A nice bonus: you can micro-adjust alignment by cracking the screw a quarter turn one way or the other to close a hairline gap—handy on tricky inside corners.

Mushrooms, plugs, and finish appearance

Composite mushrooming is always the elephant in the room. With these, it’s minimal to none in most situations. When I needed a perfectly clean surface for a visible tread nosing, I used a shallow countersink or a small pilot to keep the rim crisp. The low-profile head leaves a neat dimple that looks intentional, and in the gold finish it disappears more than you’d expect once everything’s cleaned up.

If you prefer plug systems for face-screwed decking, these aren’t a hidden fastener substitute; they’re a practical, visible fastener with a refined look. On PVC trim, a quick dab of color-matched filler makes the head vanish entirely.

Versatility beyond decking

These shine in exterior PVC and composite, but I’ve also leaned on them for interior jobs:

• Cabinet installs and fillers where a tiny head helps avoid splitting face frames.
• Hardwood transitions and thresholds where a clean, flush head matters.
• Light trim alignment during glue-ups—drive, adjust, and the underhead thread keeps joints tight without a big crater.

That said, they’re not structural screws. I don’t use them for framing, ledger attachments, or anywhere head pull-through resistance is mission-critical. Think finish and trim tasks where control and finish are the priorities.

Durability and corrosion resistance

The coating is rated for exterior use, and in my testing it behaves like it. Over a full season on an exposed stair run and on PVC fascia, I haven’t seen rust or tea staining. The gold finish stays tidy, and there’s no black streaking around the head. For severe coastal or salt-spray conditions, stainless is still the belt-and-suspenders choice; for typical exterior exposure, these have been rock solid.

Box quantity and consistency

A 725-count box is generous. On my stair rebuild (stringers, treads, risers, and skirt boards), plus some follow-up trim work, I barely crossed halfway. What I appreciate more is consistency—threads were clean, points were sharp, and I didn’t hit any heads with malformed drive recesses. No bent or bad screws in the batches I pulled.

Tips for best results

• Use a small pilot in dense composites or near sensitive edges, especially in cold weather.
• Dial down the impact for the final seating to avoid dishing softer materials.
• Keep a few extra T-10 bits handy; swap them early to preserve the recess and avoid cam-out.
• For immaculate surfaces on visible faces, touch with a countersink first or plan to dab with filler (PVC) afterward.
• Space screws consistently and keep drive speed moderate to avoid heat buildup in composite.

Where they outpace generic screws

• Cleaner finish: The trim head and underhead reverse thread noticeably reduce mushrooming compared to generic bugle-head deck screws.
• Better control: The T-10 drive and predictable bite make it easier to hit flush without skittering or cam-out.
• Alignment ability: The reverse thread under the head genuinely helps draw pieces together and fine-tune joints.

Where they’re not ideal

• Not for structural loads: The small head and #8 shank aren’t designed for heavy-duty connections.
• T-10 limitation: I’d love a T-15 for longevity, but the trim head size dictates T-10. Plan for bit replacements.
• Length constraints: At 2", they’re perfect for trim and decking skins but not for thick assemblies or layered substrates where you need deeper embedment.

Value and cost perspective

They cost more than bulk-bin deck screws, but the time savings and finish quality justify the spend. Fewer do-overs, fewer chewed edges, and fewer mushrooms to clean up add up quickly on a composite or PVC job. If you’re counting dollars per hour on site, they make sense.

The bottom line

The RT Composite trim screws hit their brief: fast, clean, low-profile fastening in composite and cellular PVC with minimal mushrooming and reliable drive performance. They’re versatile enough to cross into interior trim and cabinetry when a small, neat head is a benefit. I appreciate the consistency across the box, the exterior-ready coating, and the way the underhead reverse thread genuinely improves finish quality.

Recommendation: I recommend these for anyone regularly working with composite decking or cellular PVC trim, and for finish carpenters who want a discreet, exterior-rated fastener with excellent control. They’re not a substitute for structural screws, and the T-10 drive demands good bits and a steady hand, but the payoff is in the clean look and fewer headaches. For trim, fascia, risers, and detailed exterior work, they’ve earned a permanent place in my kit.