If you work with fasteners daily, you already know: not all screws are created equal. But here’s the catch — using the wrong system can derail an entire build. Metric or imperial? That’s the choice most engineers, builders, and procurement teams face.
And if you’re a metric washer supplier, you need to explain the difference clearly. Because your buyers rely on it.
The Two Systems in a Nutshell
- Metric screws: Based on millimeters. Sizes like M5, M6, M10. Thread pitch is usually given in millimeters as well.
- Imperial screws: Based on inches or fractions. Sizes such as #8-32 and ¼-20. Thread count (TPI — threads per inch) is the standard measure.
Simple on paper. But in practice? Confusion happens often. Especially when global supply chains mix both systems.
Why Metric Screws Dominate Globally?
Metric sizing has become the world standard. ISO (International Organization for Standardization) defines it. That means:
- Consistency: Every M6 screw means a 6mm nominal diameter.
- Ease of calculation: Engineers prefer decimal-based measurements.
- Interchangeability: Parts designed in Europe, Asia, or Canada usually default to metric.
If you’re supplying stainless steel metric screws, you’re meeting the majority of industrial and commercial demand. They fit modern designs. They’re easier to specify.
But Imperial Screws Still Hold Ground?
In Canada and the U.S., imperial screws remain common. Legacy machinery. Building codes. Older supply chains. They all keep imperial alive.
An imperial screw often comes with specifications like:
- Diameter measured in inches (#6, ¼, ½).
- Threads per inch (TPI) instead of pitch.
- Head styles — flat, pan, or oval — that match sheet metal or wood applications.
So, while metric is standard, imperial still matters. If you supply to both industries, you need both stocked.
Where Metric Screws for Metal Excel?
Metal fabrication demands precision. Misalignment or slippage can mean costly errors. Metric screws for metal are designed for:
- Tight tolerances.
- Strong clamping forces.
- Compatibility with metric washers and nuts.
Pairing screws with metric washers distributes pressure evenly and protects the metal surface. That’s why many suppliers stock washers alongside screws.
The Role of Stainless Steel
Whether metric or imperial, stainless steel remains the material of choice. Why?
- Corrosion resistance — ideal for outdoor, marine, or industrial environments.
- Strength — especially in 304 (A2) and 316 (A4) grades.
- Clean finish — preferred for visible or architectural applications.
When customers ask for stainless steel metric screws, they want both strength and longevity. If you’re advising buyers, explain the grade difference. A4 is for harsher conditions. A2 suits general use.
Sheet Metal Screws — Bridging Both Systems
Here’s where it gets interesting. Sheet metal screws are available in both metric and imperial. They’re versatile. They cut into thin metal sheets. They don’t require a nut.
Applications include HVAC, enclosures, and light fabrication. For suppliers, stocking both versions covers a wide buyer base. An HVAC contractor may still ask for #8-32 (imperial). A fabrication shop may insist on M5 (metric).
Common Buyer Questions (and How to Answer Them)
When customers reach out, here’s what they usually ask:
- “What size do I need?” → Ask what the mating part requires. Metric systems call for M sizes. Imperial uses fractions.
- “Can I mix metric washers with imperial screws?” → No. Always match systems. Otherwise, you’ll risk loose fits.
- “Which stainless grade should I choose?” → A2 (304) for indoors. A4 (316) for corrosive or marine.
- “Do I need coarse or fine threads?” → Coarse for general assembly. Fine for vibration resistance or harder materials.
Having these answers ready sets you apart as a reliable metric washer supplier — not just a reseller.
Choosing Between Metric and Imperial Screws — A Quick Guide
- Check project specs: If it’s European or Canadian-manufactured, metric dominates.
- Audit existing hardware: Older machines or U.S.-based designs may need imperial.
- Match accessories: Washers, nuts, and tools must align with the system.
- Think future-proof: If new builds are in scope, lean metric.
Why Suppliers Must Educate Customers?
Confusion between the two systems wastes time and money. A missing washer. A mis-threaded screw. A wrong bulk order. The costs add up.
That’s why suppliers like CanadaBolts list metric and imperial screws separately. Categories are clear. Specs are precise. Customers can check before ordering.
As a supplier, your role goes beyond selling hardware. It’s about guiding. Buyers trust you to clarify the metric–imperial divide.
Final Word — Don’t Guess, Choose Right
Metric or imperial — the decision isn’t about preference. It’s about compatibility. And it starts with understanding the difference.
If you’re an engineer, buyer, or contractor, confirm specs before purchase. If you’re a metric washer supplier in Canada, stock both. Highlight the differences. Advise your clients.
Looking for stainless steel metric screws or durable sheet metal screws? Order from a supplier that lists sizes clearly, stocks both systems, and ships across Canada.
Because with fasteners, accuracy isn’t optional. It’s everything.