Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Whether you're assembling electronics enclosures, maintaining industrial equipment, or tackling a precision DIY build, finding a fastener kit that stays tight under vibration is a constant challenge. Loose screws back out over time, and sourcing screws, spring washers, and flat washers separately wastes time and risks mismatched sizing. These black zinc pan head machine screws with spring and flat washers solve that problem in one ready-to-use combination set.
Each pack contains pan head machine screws paired with matching spring (split) washers and flat washers, all finished in black zinc for a uniform, corrosion-resistant appearance. Available in thread diameters M3, M4, M5, M6, and M8, with bolt lengths ranging from 5mm (≈3/16") to 50mm (≈2"), and pack sizes of 5, 10, 20, or 50 pieces to suit both small repairs and larger production runs.
These combination fastener sets are well-suited for electronics chassis assembly, computer hardware mounting, light machinery maintenance, and general-purpose metric fastening where a clean black finish and vibration resistance are required. They're a go-to choice for makers, technicians, and hobbyists who need reliable metric machine screws with washers in one convenient kit.
| Thread Standard | ISO Metric Coarse (DIN 7985 / equivalent) |
|---|---|
| Thread Diameters | M3, M4, M5, M6, M8 |
| Bolt Lengths Available | 5mm (≈3/16") – 50mm (≈2") |
| Head Type | Pan Head |
| Drive Type | See variant options / product images |
| Material | Carbon steel with black zinc electroplating |
| Finish | Black zinc (electroplated) |
| Included Hardware | Pan head screw + spring (split) washer + flat washer |
| Pack Sizes | 5 / 10 / 20 / 50 pieces |
| Corrosion Resistance | Moderate — suitable for indoor and light outdoor use |
| Country of Origin | Contact us to confirm |
| Compliance / Standards | Contact us to confirm |
As a general rule, the bolt length should equal the thickness of all materials being joined plus approximately 1–2 thread pitches of engagement beyond the nut or threaded hole. For example, if you're fastening two 5mm panels, a 12mm or 16mm bolt is typically sufficient. Always measure your stack-up — material thickness plus washer thickness — before selecting a length. For inch reference: 10mm ≈ 3/8", 20mm ≈ 3/4", 30mm ≈ 1-3/16", 50mm ≈ 2".
These are generally rated as standard-strength machine screws. Exact tensile and shear values depend on the specific diameter and length. For structural or safety-critical applications, please contact us to confirm the mechanical grade before ordering.
The black zinc plating provides moderate corrosion resistance suitable for indoor and light-duty outdoor use. For prolonged outdoor exposure, high-humidity, or marine environments, a stainless steel fastener is typically recommended. If you need outdoor-rated black fasteners, contact us for alternatives.
These screws use the ISO metric coarse thread standard (M3, M4, M5, M6, M8). They are compatible with standard metric nuts, threaded inserts, and tapped holes following ISO 68-1 specifications. They are not compatible with UNC or UNF inch-thread fasteners.
Each pack includes pan head machine screws, spring (split) washers, and flat washers — all in the selected size and quantity. The combination set is designed to be used together for a secure, vibration-resistant fastening without needing to source washers separately.
Using both washers together is a widely accepted practice: the flat washer distributes the clamping load across a larger surface area to protect the workpiece, while the spring (split) washer provides a locking action that resists loosening from vibration. This combination is commonly used in electronics assembly, machinery, and general mechanical applications.
Pan head machine screws typically require a Phillips (#1 or #2 depending on size) or a flat-blade screwdriver. Some variants may use a hex socket or Pozidriv drive — check the product images or contact us to confirm the drive type for your selected size.
