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B&Q£5.04Visit shop B&Q - M4 Pozidriv Countersunk Zinc-Plated Carbon Steel Machine Screw & Nut (Dia)4mm (L)20mmPack Of 20
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The Diall Machine Screw & Nut set is an ideal choice for DIY enthusiasts and homeowners needing a reliable fastening solution for assembly tasks involving metal, plastic, or wood projects. These M4 x 20mm fasteners offer a professional silver finish and a flush-fitting countersunk head design, providing both aesthetic appeal and structural integrity. While they are highly durable, they are specifically sized for M4 applications, so they may not be suitable for projects requiring heavier-duty bolts or different thread diameters.
| Colour | Silver |
|---|---|
| Brand | Diall |
These are primarily designed for indoor DIY tasks. While the finish is durable, prolonged exposure to moisture may lead to corrosion.
You will need a Phillips screwdriver and a wrench or pliers to hold the nut in place while tightening.
No, these are machine screws intended for assembly tasks, not for supporting high-load wall-mounting applications.
The screw is an M4 size, which has a nominal thread diameter of 4mm.
The pack includes screws and nuts, but washers are not included. If your project requires them to distribute pressure, you should purchase M4 washers separately.
Ensure the screw and nut are aligned perfectly straight and that no debris is lodged in the threads.
Ensure you are using the correct size screwdriver bit and apply firm, downward pressure while turning.
These are 20mm fasteners; if they do not reach through your material with enough clearance to attach the nut, you will need a longer screw length.
To achieve the best results, use a Phillips screwdriver or a compatible hex driver that matches the screw head size to avoid stripping the drive. These fasteners are designed for use with M4-threaded nuts; do not force them into different thread patterns as this will damage the threads. For installation in hard materials like metal, use a small amount of lubricant on the threads to prevent binding. To maintain the silver finish and prevent potential rust, store the screws in a dry, low-humidity environment. If used in a high-vibration area, consider using a thread-locking compound to prevent the nuts from loosening over time.
