The Tetra Inspection blog is the company's quality control resource hub — practical, field-tested guides on pre-shipment inspections, factory audits, supplier verification, and sourcing strategy, written by an independent third-party inspection network that has completed 20,000+ inspections across 45 countries since 2014. Browse the categories and search below to find the guidance you need before your next production run ships.
Quality Control Blog
Expert insights on quality control, sourcing strategies, compliance standards, and industry best practices to help you protect your supply chain.
Gray Scale (Grey Scale): Meaning & How to Use It
The gray scale (grey scale) is the 1–5 standard inspectors use to grade colour change and staining in textile colour-fastness testing. Here is what each grade means and how to use it.
Amazon FBA Label Requirements: FNSKU, Shipping & Packaging Guide
Amazon FBA label requirements explained — FNSKU label sizes, shipping (box ID) labels, suffocation warnings, and carton limits to keep your shipment from being rejected.
Mold Prevention Strategies: How to Prevent Mold on Products
Mold is a type of fungus that can be categorized as one of the most dangerous microorganisms for your brand. You might be wondering how a seemingly harmless strand of Fungus can affect your brand image.
Proposition 65 (Prop 65): What the Warning Means & Who Must Comply
According to the Prop 65 regulation: “Any person doing business in California who knowingly and intentionally exposes California consumers to one of over 1,000 listed chemicals known to cause cancer or reproductive toxicity must give a “clear and reasonable” warning to those consumers.” Proposition 65 is t
AQL Levels and Inspection Levels: How to Choose the Right One
For every product manufactured, whether in batches or not, there is always a need to inspect them, as to whether or not the manufacturers meet the standards set for the product. Most manufacturers mass produce in batches. It would be a big waste of time, money and energy to go through all products o
China Supplier Verification Audit
Most importers prefer to work with factories instead of placing their order to a trading company or middle man. However, almost all Chinese suppliers claim that they are factories, including Alibaba suppliers, although, in reality, they are commercial companies or worse; they are scammers.
Amazon QC: FBA Quality Control & Supplier Inspections for Sellers
As an Amazon seller quality control should be your number one priority. It has great benefits when your ordered good or products are pre-inspected before shipment to avoid stories that touch the heart. Once your products are paid in full and shipped, you are beyond the point of no return.
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Tetra Inspection blog: frequently asked questions
What does the Tetra Inspection blog cover?
The Tetra Inspection blog publishes in-depth guides on third-party quality control — pre-shipment inspections, factory audits, supplier verification, social compliance, and product-specific QC checklists — for importers sourcing from China and across Asia.
Who writes the Tetra Inspection blog?
Articles are produced by Tetra Inspection's quality control team and reviewed by the company's founder, drawing on field data from a network of 500+ inspectors working across 45 countries.
Is Tetra Inspection an independent third-party inspection company?
Yes. Founded in 2014, Tetra Inspection is an independent third-party inspection network that has completed 20,000+ inspections for 2,000+ clients, with flat per-man-day pricing and photo inspection reports delivered within 24 hours.
How do I find a specific topic on the Tetra Inspection blog?
Use the category filters and search box on this page to browse articles by topic — for example pre-shipment inspection, factory audits, or industry-specific quality control guides.