ScrewSourceScrew Guides
Explained by our knowledge partner Screw Xiaoer — plain-language fastener knowledge for buyers, with the exits that matter — the products and the RFQ.
Screw Strength Grades Explained: 4.8 / 8.8 / 12.9 and A2/A4
How to read property class markings on carbon steel screws, what A2-70 means on stainless, why the numbers are not a quality ranking, and what to confirm when you order by grade.
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Metric Screw Sizes & Thread Pitches (M2–M12 Quick Reference)
A plain table of the ISO metric coarse and fine pitches you will actually meet in small fasteners — plus tapping drill sizes, how to read an M-size callout, and the traps that cause wrong-thread orders.
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How to Read Fastener Standards: DIN vs ISO vs ANSI vs GB
What a standard number actually promises, why DIN 912 and ISO 4762 are not the same thing, and how to source by standard without over-committing your design.
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Understanding Screw Head Types — Pan, Flat, Socket Cap & More
Head geometry decides how a screw sits, spreads load and looks after assembly — a field guide to the head types in our catalog and when to use each.
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Self-Tapping vs Machine Screws: What's the Difference?
The thread decides everything — how each screw type grips, where each belongs, and why getting this one detail right saves the most rework.
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Nickel Plated vs Zinc Plated Screws — The Practical Difference
Brightness, corrosion behaviour, cost and typical uses of the two most common screw finishes — and how to specify the one you actually need.
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How We Quote: What to Include in Your Fastener RFQ
Inside our sourcing workflow — what happens after you press Send, and the exact details that make your first quotation usable instead of a question list.
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How to Specify a Screw: Diameter, Length, Head & Drive
The five details that turn "I need some screws" into a quotation you can actually compare — plus the shorthand buyers use to write them down.
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304 Stainless vs Carbon Steel Screws: Which Should You Buy?
Corrosion resistance, strength, appearance and price — a practical way to choose between stainless and plated carbon steel screws for your application.
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