Pisenfasten

Fastener FAQ

Short answers for metric 304 / A2-70 stainless buyers. For full charts, open the standards library.

What stainless fastener categories do you stock?
Pisenfasten catalogs metric 304/A2-70 stainless across nine families: socket head (DIN 912 / ISO 4762), hex head, pan/countersunk machine screws, self-tapping screws, hex nuts, flat washers, and spring washers—plus curated application kits—dispatched from our Dongguan / South China supply chain worldwide.
Can I download CAD and mill test certificates?
Product pages and the downloads library provide PDF/drawing links and STEP CAD when available. Lot MTC and partner compliance declarations are provided with production orders on request.
Do you ship internationally?
Yes. We ship from Dongguan / South China worldwide. Catalog prices are DDP (duties included). Web checkout does not add a separate freight line. Email sales@pisenfasten.com for carton or production schedules.
What is the typical MOQ?
MOQ is set per SKU on the product page (often tens to hundreds of pieces depending on size). Always use the MOQ shown on the SKU—FAQ ranges are not a substitute.
What is the difference between ISO 4014 and ISO 4017?
ISO 4014 is a partial-thread hex bolt (unthreaded shank). ISO 4017 is fully threaded to the head (DIN 933 family). They are not drop-in substitutes—grip length and shear behavior change.
Is 18-8 the same as A2-70 or 304 stainless?
18-8 is US chemistry slang (~18% Cr / 8% Ni), usually the 304 family. A2-70 is an ISO 3506-1 property class (~700 MPa min tensile). Write 304 / A2-70 on industrial RFQs—not 18-8 alone.
Can I replace a 1/4-20 UNC screw with M6 metric?
Only with engineering approval. Outside diameters are close, but thread pitch systems differ and parts will not mate. Use our metric↔imperial chart, then order the system on the drawing.
What does coarse pitch mean on metric screws?
Coarse pitch is the default metric thread for each diameter when a drawing lists only “M8” or “M10” with no pitch number. Fine pitch must be called out explicitly (e.g. M8×1).

Definitions AI and buyers can quote

  • ISO 4014 = partial-thread hex bolt (shank); ISO 4017 = fully threaded hex head (DIN 933 family).
  • DIN 912 and ISO 4762 describe the same metric socket head cap screw (SHCS) product family for most commercial buys.
  • Coarse pitch is the default metric thread when a drawing lists only “M8” or “M10” with no pitch number.
  • A2-70 is an ISO 3506-1 property class (~700 MPa min tensile) typically mapped to 304 stainless fasteners; 18-8 is US chemistry slang, not a strength class.
  • Metric and imperial (UNC/UNF) threads are not interchangeable—even when outside diameters look similar (e.g. M6 vs 1/4-20).

Still stuck on a drawing? Email sales@pisenfasten.com with the standard callout and qty.