Black Plastic Phillips Countersunk Machine Screws — Lightweight, Non-Conductive, Corrosion-Resistant
If you've ever stripped a metal screw near a circuit board, cracked a plastic housing with an over-torqued fastener, or watched a steel screw rust out in a damp enclosure — you know the frustration. Engineers, makers, and repair technicians who work with electronics, lightweight assemblies, and corrosion-prone environments need a fastener that won't fight back. These black plastic Phillips flat head countersunk machine screws are built for exactly those situations.
Each screw is molded from black nylon (polyamide), offering a clean flush-mount countersunk profile when installed in a properly prepared countersunk hole. Available in thread diameters M2.5, M3, M4, M5, M6, and M8, with lengths ranging from 5mm (≈3/16") to 40mm (≈1-9/16"). Packing options of 10, 20, 50, 100, and 500 pieces let you order exactly what your project or production run requires.
Typical use cases include PCB and electronics enclosure assembly, RC hobby and drone frame fastening, aquarium and hydroponic equipment mounting, and lightweight panel or cover attachment — anywhere a black plastic Phillips countersunk machine screw delivers a cleaner, safer result than metal.
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Compatibility: ISO metric thread standard — fits standard metric nuts, threaded inserts, and tapped holes. M2.5–M8 diameters. Not compatible with UNC/UNF inch threads. Verify your countersink angle matches the screw head profile before ordering.
✅ Key Features of These Black Plastic Phillips Countersunk Machine Screws
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⚡Non-Conductive Material — Nylon construction eliminates electrical conductivity, making these black plastic machine screws safe for PCB mounting, electronics enclosures, and any application where metal fasteners risk short circuits.
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🛡️Corrosion-Resistant by Nature — Unlike steel or zinc-plated screws, nylon does not rust or oxidize. Suitable for damp environments, aquarium equipment, and outdoor-protected installations without surface treatment.
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⚖️Lightweight Construction — Nylon is significantly lighter than metal, reducing overall assembly weight — a key advantage in drone frames, RC vehicles, and portable electronics where every gram counts.
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🔩Flush Countersunk Head Profile — The flat Phillips countersunk head sits flush with or below the surface when installed in a properly countersunk hole, providing a clean finish for panels, covers, and visible assemblies.
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📐Wide Size Range — M2.5 to M8 — Six thread diameters and lengths from 5mm to 40mm cover the majority of light-duty metric fastening needs, from miniature electronics to mid-size enclosure panels.
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📦Flexible Pack Quantities — Order 10 pcs for a quick repair, or 500 pcs for production-scale assembly. Bulk packs reduce per-unit cost for workshops, manufacturers, and resellers stocking black plastic countersunk screws.
📐 Technical Specifications — Black Plastic Phillips Countersunk Machine Screws
| Material |
Black nylon (polyamide) — non-conductive, non-magnetic |
| Head Type |
Flat head (countersunk), Phillips (cross) drive |
| Thread Standard |
ISO metric coarse thread |
| Thread Diameters |
M2.5, M3, M4, M5, M6, M8 |
| Available Lengths |
5mm (≈3/16"), 6mm (≈1/4"), 8mm (≈5/16"), 10mm (≈3/8"), 12mm (≈15/32"), 14mm (≈9/16"), 15mm (≈19/32"), 16mm (≈5/8"), 20mm (≈25/32"), 25mm (≈1"), 30mm (≈1-3/16"), 35mm (≈1-3/8"), 40mm (≈1-9/16") |
| Packing Options |
10 PCS / 20 PCS / 50 PCS / 100 PCS / 500 PCS |
| Color |
Black |
| Drive Type |
Phillips (PH0 for M2.5–M3; PH1 for M4–M5; PH2 for M6–M8 — verify with your driver set) |
| Recommended Use |
Light-to-medium duty; electronics, enclosures, hobby assemblies, panels |
| Corrosion Resistance |
Inherent — no plating required |
| Country of Origin |
See variant options |
| Certifications |
Contact us to confirm |
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Note: Plastic screws are not suitable for high-torque, structural, or load-bearing applications. Always verify thread engagement depth and countersink angle compatibility before installation. If you need a specific length or diameter not shown, contact us to confirm availability.
❓ Frequently Asked Questions
How do I choose the right length for my black plastic countersunk machine screw?
A general rule: the screw length should equal the thickness of the material being fastened plus enough thread engagement in the receiving part — typically 1.5× the screw diameter. For example, an M4 screw generally needs at least 6mm of thread engagement. If you're countersinking flush, measure the countersink depth and add the required thread engagement. When in doubt, size up. Available lengths range from 5mm to 40mm (≈3/16" to 1-9/16").
How strong are plastic machine screws compared to metal ones?
Nylon machine screws are generally rated for light-to-medium duty applications. They are not intended for high-torque or structural load-bearing joints. They are typically used in electronics enclosures, PCB mounting, and lightweight assemblies where metal screws could cause galvanic corrosion or electrical interference. For structural joints, metal screws are recommended.
Are these screws suitable for outdoor or wet environments?
Yes — nylon plastic screws are inherently corrosion-resistant and will not rust. They are generally suitable for damp or mildly wet environments such as aquarium equipment, hydroponic setups, and outdoor-protected enclosures. However, prolonged direct UV exposure may cause gradual degradation over time. For long-term outdoor use, consider UV-protected installations.
What thread standard do these machine screws use — are they compatible with standard metric nuts?
These screws follow the ISO metric coarse thread standard (M2.5, M3, M4, M5, M6, M8). They are compatible with standard metric nuts, threaded inserts, and tapped holes of the same diameter and pitch. They are not compatible with UNC or UNF inch-standard threads.
What Phillips driver size do I need for these screws?
Use the correct Phillips bit size for the screw diameter — typically PH0 for M2.5–M3, PH1 for M4–M5, and PH2 for M6–M8. Using an incorrect bit size may strip the plastic head. Apply moderate, steady torque; nylon heads are more susceptible to cam-out than metal heads.
Can I use these screws in electronics or PCB assemblies?
Yes. Black plastic (nylon) Phillips countersunk machine screws are widely used in electronics and PCB assemblies because they are non-conductive and non-magnetic. They eliminate the risk of short circuits and are safe to use near sensitive components, transformers, and high-frequency circuits.
How do I decide between 10, 50, 100, or 500 pcs packing?
Choose 10–20 pcs for one-off repairs or prototyping. Choose 50–100 pcs for small production runs or workshop stock. Choose 500 pcs for bulk manufacturing, assembly lines, or resale. Larger packs offer a lower per-unit cost and reduce reorder frequency.
🛒 Select your thread diameter, length, and quantity above, then add to cart — ships from our US warehouse.
