Stainless Steel Hex Head Timber Screws for Harsh Outdoor Environments
Our A4 Stainless Steel Hex Timber Screws are built to tackle the most demanding outdoor conditions – from coastal builds to chemically treated timbers like Green Oak.
Designed as a high-strength alternative to coach screws, these heavy-duty fixings provide a secure timber-to-timber hold without rusting or reacting with the wood.
The hex head with a fixed washer ensures a strong clamping force, while the sharp slash point and helix shank make driving fast and smooth – even in dense hardwoods or composite timber.
Key Features
✔ Hex head with integrated washer – strong torque with a clean, flush finish
✔ A4 Stainless Steel construction – ultimate corrosion resistance, perfect for coastal or high-moisture environments
✔ Helix shank – clears debris as it drives, reducing resistance and increasing hold
✔ Slash point – cuts in fast and reduces splitting near edges
✔ 25° sharp tip – quick start and improved thread engagement
✔ Deep thread profile – high pull-out resistance for a reliable structural hold
✔ No pilot hole required in most cases – just drill and drive
How to Use
- Mark your fixing points and align the timbers.
- In softwood or general timber, these screws drive straight in with no pilot hole. For dense hardwood or edge work, a small pilot may help.
- Use an impact driver or socket wrench to drive the screw – the fixed washer clamps down tight, and the deep thread bites securely.
- Tighten until the head sits flush – no need for extra washers or finish prep.
Perfect for:
- Green Oak beams or posts
- Hardwoods or pressure-treated timbers
- Retaining walls, raised beds, structural landscaping
- Timber projects near the coast or in wet environments
What Sizes Are Available?
These A4 stainless hex screws come in the most popular sizes for landscaping, timber framing, and structural work:
Available sizes:
6.7 x 50mm, 6.7 x 75mm, 6.7 x 100mm, 6.7 x 125mm, 6.7 x 150mm, 6.7 x 200mm, 6.7 x 250mm, 6.7 x 300mm
What Size Screw Do I Need?
To get a solid hold, go with a screw that’s 2.5 to 3 times longer than the timber thickness you’re fixing through.
- Fixing a 50mm board or sleeper? Go for 125mm or 150mm screws
- Securing structural posts or beams? Use 200mm or longer
- For most general jobs, 75mm, 100mm, and 150mm are ideal starting points
Why Choose Stainless Steel?
Unlike coated screws, these fixings are made from solid A4 stainless steel – ideal when long-term durability is essential. They're the right choice when:
- You're working near the coast or water
- You’re fixing Green Oak, Accoya, or other chemically treated timber
- You want peace of mind that your fixings won’t rust, stain, or fail over time
Other coatings can chip or degrade – stainless steel holds up no matter the conditions.
Why Buy Timber Screw - Hex - A4 Stainless Steel from Fast Fixings Online?
When you buy your Timber Screw - Hex - A4 Stainless Steel from Fast Fixings Online, you’re getting more than just great fixings. We offer free next working day delivery on orders over £60, so your materials arrive when you need them. You can create a free account to save time on repeat orders, and if you join our VIP Rewards Club, the more you spend, the more you save. It’s our way of giving something back to loyal trades and customers who keep coming back.