Pack of 40 Koelner/Rawlplug construction screws, partial thread with a countersunk head, size 3.5 × 25 mm. These screws are intended for wood-to-wood connections and light construction tasks where a flush finish is required. The partial thread and tapered countersunk head allow the screw to pull pieces together while the head sits flush in a countersunk hole. The size 3.5 × 25 mm is suitable for thin boards, trims, and many furniture assembly operations. The product is compatible with standard drills and screwdrivers commonly used in carpentry and renovation work.
Advantages
The partial thread design provides strong clamping of joined wooden parts while reducing the risk of over-threading through thin materials. The countersunk head ensures a flush surface that can be concealed or covered by filler or caps. Supplied in a pack of 40, the set is convenient for small to medium projects and reduces the need for frequent reordering. The screws are designed for ease of use with common hand and power tools.
Suitable for
- General carpentry and joinery tasks
- Furniture assembly and repair
- Interior trim, molding, and skirting installation
- Renovation and light construction projects
When it may not be suitable
These screws are intended for light to medium wood applications; they are not designed for heavy structural loads or exterior use unless additional corrosion protection is specified. For very hard dense timbers or load-bearing connections, longer or thicker fasteners or specialty structural screws should be considered.
Key specifications
- Quantity: 40 pieces per pack
- Thread type: partial (incomplete) thread
- Head type: countersunk (flat, conical seating)
- Nominal size: 3.5 × 25 mm (diameter × length)
- Drive: compatible with standard screwdrivers and drills
How to use
Pre-drill a countersink or pilot hole appropriate to the material density and screw diameter to prevent splitting, especially near edges. Position the parts to be joined, insert the screw through the top piece so the unthreaded shank can draw the two pieces together, and drive the screw until the head is flush with the surface. For a neater finish, use filler, caps, or a plug to conceal the countersunk head if desired. Use a compatible screwdriver bit or driver setting to avoid cam-out and damage to the head.
What to consider before purchase
- Confirm the screw length and diameter suit the thickness and type of wood you intend to fasten
- Check whether corrosion resistance is required for your application (e.g., exterior or humid environments)
- Ensure your tools accept the screw drive type and size
Usage recommendations
For best results, use appropriate pilot and countersink bits matched to the 3.5 mm diameter and the wood species. When joining thin boards, watch the screw penetration depth to avoid breakthrough. Keep spare screws from the same pack for consistent finishes across the project.
