Fixing and buying guide
ST500804-ST Ulti-mate II Professional Woodscrew PoziSquare Double Csk Z & Y 5mm X 80mm - (10g) - 350 Tub
What you are buying
This is a trade pack of 350 professional-grade woodscrews, 5mm diameter and 80mm long. Each screw features a PoziSquare double countersunk head, type-17 point, and a wide single thread for rapid insertion and strong holding power. The pack includes two Stick-Fit driver bits matched to the PoziSquare recess, saving you time on site.
- Quantity: 350 screws per tub
- Size: 5mm x 80mm
- Head type: Double-angle countersunk (PoziSquare)
- Point: Type-17 for hard timber penetration
- Finish: Zinc and yellow passivated (Z & Y)
- Included: 2x Stick-Fit driver bits
Who these screws are for
Ulti-mate II screws suit professional carpenters, joiners, and experienced DIY users working with hardwoods and dense softwoods. The trade tub size and included driver bits make them cost-effective for high-volume work. They are ideal for structural timber connections, cabinetry, decking, and external joinery where corrosion resistance and holding power matter.
- Professional and trade users
- Hardwood and difficult timber applications
- High-volume fixing projects
- Interior and exterior work
Compatibility and sizing
At 5mm diameter and 80mm length, these screws suit timber thicknesses of 50-60mm for through-fixing, or 60-70mm for face-fixing into solid wood. The type-17 point and wide thread mean they drive efficiently without pre-drilling in most softwoods, though pre-drilling is recommended in hardwoods and near edges to prevent splitting. The PoziSquare head works with the supplied Stick-Fit bits and standard PoziSquare drivers.
- Suitable for 50-70mm timber thicknesses
- Pre-drill hardwoods and near timber edges
- Compatible with PoziSquare driver bits
- Use supplied Stick-Fit bits or equivalent
Before you fix
Check that your timber is dry and free from knots or obstructions along the screw line. Ensure your drill or driver has a charged battery and that the PoziSquare bit is in good condition and seated fully in the screw head recess. For hardwoods, mark your fixing points and pre-drill with a pilot hole slightly smaller than the screw shank. Inspect the double countersunk head to confirm it will sit flush with your timber surface.
- Inspect timber for dryness and defects
- Check driver bit condition and fit
- Pre-drill hardwoods and near edges
- Ensure countersunk head will sit flush