Manufacturers and trading partners in China will do what you define. Vague marketing language or incomplete specs produce multiple rounds of clarification, unexpected cost, and quality gaps at the inspection stage. This field note lists the technical, material, and acceptance criteria a China-ready spec must include so suppliers can quote and execute against shared expectations.

Start with the customer requirement — but translate it into measurable criteria

A customer may say "waterproof" or "premium finish." Those are outcomes, not production instructions. Convert outcomes into measurable attributes:

  • Target performance (e.g., waterproof to IPX7, 1m immersion for 30 min).
  • Quantified appearance goals (e.g., gloss 70 ±5 GU measured with a 60° meter; no orange peel visible at 30 cm under 500 lux).
  • Durability targets (e.g., 50,000 cycles mechanical switch life; colorfastness ΔE ≤ 2 after 500 rubs).

Link each outcome to a test method and acceptance criterion. If you require an IP rating or specific mechanical life, name the standard and the pass/fail threshold.

Technical drawings and tolerances

A drawing is the contract. Provide:

  • Fully dimensioned CAD or 2D drawings with geometric dimensioning and tolerancing (GD&T) where form, fit or function matters.
  • Material callouts with grades (e.g., ABS UL-94 HB, or PA66 GF30) and preferred suppliers if critical.
  • Surface finish specifications (e.g., anodize 15–20 µm, color reference RAL 9003; matte finish Ra 0.6 µm).
  • Critical tolerances and inspection methods (e.g., flatness ≤ 0.2 mm measured with a 3-point fixture).

Avoid tolerances listed as "to be agreed" — that invites assumptions. If you need looser tolerances in non-critical areas, state them.

Standards and regulatory references

Name applicable international and national standards (ISO, IEC, ASTM, GB). If the product will be exported, identify destination market regulations that will affect design, marking, or testing. For importers, official guidance on documentation and regulatory checks exists and should be consulted when planning shipments [1].

When citing a standard, include the exact clause or test method you expect the supplier to follow (for example: "IEC 60529 — IPX7 test, clause 6.3 immersion method"). This removes ambiguity about which edition or clause applies.

Materials, components and approved sources

List critical components and any approved vendors or part numbers. For electronic products specify:

  • Component classification (e.g., electrolytic capacitor, 220 µF ±20%, 35 V, 105 °C, low ESR) and approved BOM alternatives.
  • RoHS or REACH requirements and required declarations.
  • Plating, solder alloy, adhesive type and cure profile if they affect performance.

If substitution is allowed, give an explicit approval process for alternatives.

Testing and inspection: methods, sample sizes, and acceptance criteria

Define what will be tested, how, and the acceptance criteria:

  • Pre-production samples: expected to meet full spec, signed off before mass production.
  • Production testing: which percentage/lot will be function-tested (e.g., 100% electrical test, 1% destructive test per lot).
  • Visual inspections: AQL level (e.g., AQL 1.5 for critical defects, inspected per GB/T 2828.1 or ISO 2859-1). If you prefer a different sampling plan, state it and reference the standard.
  • Third-party lab tests: list accredited labs or test reports required on shipment (e.g., CB test report, SGS/Intertek reports for performance tests).

Clear pass/fail definitions prevent post-shipment disputes. For example: "Crack observed under 10x magnification is critical; any crack = reject."

Acceptance, rework and non-conformance handling

Define the process for OOS (out of specification) items:

  • Who assesses non-conformances (supplier QC, buyer inspection, independent lab)?
  • Remedy options: rework to spec with documented procedure, replacement, or price credit.
  • Limits on rework (e.g., no rework allowed for structural failures; cosmetic rework allowed up to 5% of shipment with documented before/after photos).

Require root-cause analysis for repeated failures and an 8D or corrective action plan for major quality escapes.

Packaging, marking and traceability

Specify packaging to protect the product and comply with the destination market (e.g., fumigation rules for wood pallets). Include:

  • Inner and outer packing materials, dimensions, and protective requirements.
  • Label content and placement: product name, model, serial/batch number, country of origin, handling marks.
  • Barcode or data matrix requirements for logistics.

Traceability requirements should specify what data the supplier must retain and for how long (e.g., component lot numbers traceable for 3 years).

Checklist: Minimum items to include in a China-ready specification

  • Product description and intended use
  • Drawings with GD&T and tolerances
  • Material specs and part numbers
  • Performance metrics with test methods and acceptance criteria
  • Applicable standards and clause references
  • Inspection plan (sampling, AQL, test frequency)
  • Packaging, marking, and traceability requirements
  • Non-conformance handling and required documentation
  • Pre-production sample approval and timeline

Realistic next action

Create a two-page spec cover sheet that lists the items above and attaches the drawing and BOM. Send it to your shortlisted suppliers with a request: "Confirm ability to meet each line item and identify any exceptions within 5 business days." Require a stamped capability statement and a costed quotation that references this spec. Use the supplier responses to schedule a pre-production sample and define the first inspection.

Finally, remember that regulatory requirements for imports and testing vary by destination; consult official guidance and qualified local advisors for compliance and customs documentation before shipping [1].

References

[1]: https://trade.ec.europa.eu/access-to-markets/en/content/guide-import-goods "European Commission — Guide for import of goods"