Tech Packs for Manufacturing in China: What to Include

A tech pack is a technical package: the complete, version-controlled document that tells a factory exactly how to make your product. It includes technical sketches, a bill of materials, measurement specs, construction details, colorways, artwork and labels, packaging requirements, QC standards, and a revision log. Chinese factories treat the latest signed tech pack as the contract for what gets built, which means an incomplete one is the most common root cause of "the sample was right, but production was wrong."

Most importers assume defects come from sloppy factory work. Often they come from an incomplete instruction: the factory built exactly what the documents described, and the documents didn't describe enough. If you want predictable mass production in China, the tech pack is where predictability starts.

Building one from a design idea is where many first-time importers get stuck. CN Ally helps product owners turn rough concepts into manufacturer-ready specification documents, then carries those specs through factory matching and sampling so nothing gets lost in translation. But whether you build it yourself or get help, you need to understand what goes inside, because you'll be the one approving it.

What a tech pack actually is (and what it isn't)

Short for "technical package," a tech pack is the master document a designer or product owner prepares before manufacturing, and the manufacturer produces the final product from it. Good factories in China will often refuse an incomplete brief but accept a comprehensive tech pack, because it removes the guesswork that causes expensive rework. One industry guide calls it the "final instruction manual" that passes through the supply chain, and it "leaves no room for dispute" because it forms the benchmark your product gets judged against (source).

A tech pack is not a mood board, a design brief, or a spec sheet, though it's related to all three. A design brief explains the idea; a tech pack explains the execution, and factories can quote and build from execution detail. The factory design brief guide covers the idea side; this guide covers the instruction side.

It's also not a bill of materials, a confusion that costs people real money. The BOM is the ingredient list: fabrics, components, trims, labels, packaging materials, quantities, costs. The tech pack is the full recipe: how those ingredients combine, in what order, to what dimensions, finished in what way. A BOM lives inside the tech pack as one of its most important sections.

Why factories treat your tech pack as the contract

Accurate quoting depends on it. A factory that receives vague descriptions pads the quote or guesses. A factory that receives a complete tech pack calculates material consumption, labor time, and tooling needs precisely, because every factory prices the same documented product.

It becomes the dispute benchmark. When a production run arrives with the wrong stitching or a different zipper, the question isn't what anyone "thought" the product should be. It's what the approved tech pack says. If the defect contradicts the tech pack, you have standing to demand a remedy. If the tech pack never specified the detail, the factory has a defensible position. Experienced importers obsess over the document before production, not after.

It survives personnel changes and language gaps. Your contact at the factory might leave. The production manager reading your file may not speak English. The tech pack, built from drawings, standardized tables, and international color references, communicates through numbers and diagrams rather than prose, and the document that needs the fewest words translated is the one least likely to be misread.

It compounds over time. A good tech pack gets reused for reorders, variations, and second factories. Each repeat order starts from a known-good instruction set instead of a fresh conversation.

The sections every tech pack needs

No two tech packs are identical, but the complete ones share the same skeleton:

Section · What it contains

• Cover page: Product name, style number, season, version number and date, contacts
• Technical flats: Front, back, side, and detail views with close-up callouts
• Bill of materials: Every fabric, component, trim, thread, label, and packaging material
• Measurement specs: Dimensions for every size, with tolerances on each measurement
• Grading rules: How each size scales from the base size
• Construction details: Seam types, stitch counts, assembly order, finishing methods
• Colorways: Every colorway with standardized color references per component
• Artwork and labels: Print/embroidery files, logo placements, care label content and positions
• Packaging specs: Folding, polybags, cartons, barcodes, shipping marks
• QC standards: Critical checkpoints, testing requirements, compliance references
• Revision log: Numbered versions, dates, what changed, who approved

The sections below explain what belongs in each and what goes wrong when it's missing. Start with a cover page carrying the style name and number, season, version number and date, and contacts for both sides, and repeat the style number and version in every page header, so a loose sheet is never ambiguous and nobody cuts fabric from revision 3 when you approved revision 5.

Technical flats

Flat sketches are proportioned line drawings showing the product as if laid flat: front, back, and side or detail views. Unlike fashion illustrations, flats are technical documents. Every seam, pocket, closure, pleat, and design line appears, with callouts for details needing explanation ("reinforced bartack at pocket corners," "contrast topstitch 5mm from edge"). A missing view is an unanswered question, and unanswered questions get answered by the factory's best guess. If your product has an interior (a lined jacket, a bag with pockets, a device with a battery compartment), include interior views too.

The bill of materials

Every BOM row should carry the same columns: component name, material or fiber content, weight or thickness, color reference, supplier or source, quantity per unit, and placement. Nothing is "TBD": a row that says "zipper: TBD" is a decision the factory will make for you. And every material gets a verifiable reference, a swatch number, a Pantone code, a supplier article number. Names like "soft cotton" are feelings, not specifications.

Measurement specs and tolerances

The measurement spec sheet lists every critical dimension for every size, usually in a grid with sizes across the top and measurement points down the side. For apparel: chest, waist, hip, lengths, widths, rises. For hard goods: overall dimensions, wall thicknesses, hole diameters, thread specs.

The column most importers skip is the tolerance, the acceptable variance on each measurement. A chest width of 52 cm means nothing without knowing whether 51.5 is acceptable. Setting a tolerance on every measurement is how you calibrate quality against cost deliberately instead of discovering the tradeoff in a failed inspection. The product specification writing guide covers the mechanics; the tech pack is where those specs live.

Grading and construction

Grading rules define how the product scales between sizes: how much the chest grows from M to L, how the length changes, which measurements stay fixed. Without grading, a factory scales by feel, and "feel" produces sizes that fit nothing like the sample.

Construction details describe assembly: seam types, stitches per inch or centimeter, seam allowances, the order of operations, edge finishes. For electronics and hard goods, this becomes the assembly sequence: component install order, torque specs, adhesive cure times, cable routing. A product that looks right but falls apart was usually assembled in the wrong order or with the wrong joinery, both of which belong in the tech pack.

Colorways, artwork, and labels

Every colorway needs standardized references, and the industry standard is Pantone. Each component gets its own code: shell fabric Pantone 19-4052, thread to match, zipper tape in a contrast color with its own reference. "Navy blue" describes about forty different colors. A Pantone code describes one.

Artwork covers prints, embroidery, laser etching, and debossing: the actual files, placement dimensions measured from fixed reference points ("12 cm below the neckline seam," not "centered"), size, thread or ink colors, stitch density for embroidery. Labels need content and placement: main, size, and care labels with legally required fiber content and care instructions, plus country-of-origin marking. Labeling mistakes are among the most common causes of customs and retail rejections, and they're entirely preventable here.

Packaging and QC standards

Packaging specs cover folding method, polybag thickness and print, hang tags and barcodes, inner boxes, master carton dimensions and markings. Packaging is part of the product as delivered; a crushed retail box is a defective delivery even when the product inside is perfect.

The QC section states how quality gets verified: critical measurements, what gets tested and against which standard, acceptable quality limits, compliance certifications. This section is the bridge to inspection: your golden sample and the tech pack together define what "correct" means on inspection day.

The revision log

Every change gets a numbered entry: version, date, description, reason, and who approved it on each side. Products evolve between the first sample and mass production, and without a log nobody can say with certainty which combination of decisions the current run represents. With one, "which version did we approve?" has a one-line answer.

Tech packs beyond apparel

The term "tech pack" comes from apparel, but the concept covers every manufactured product. For hard goods and electronics, the equivalent is often called a manufacturing specification package: complete instructions a factory can quote and build from (source), covering materials, dimensions, tolerances, assembly instructions, and relevant standards.

The sections translate directly. Technical flats become engineering drawings and 3D renders. The BOM becomes a component list with part numbers and approved vendors. Construction becomes the assembly sequence with torque specs and adhesive schedules. Colorways become surface-finish specs: texture standards, gloss levels, anodizing colors. The one addition: electronics usually need schematics, firmware versions, and test procedures that apparel never touches. If your factory can't produce or review those, you need a development-capable partner, not just a production factory.

The mistakes that cause real defects

Incomplete tech packs don't cause vague problems. They cause specific defects, and the mapping is predictable enough to use as a checklist.

Tech pack mistake · Defect it causes · Where it shows up

• Missing or incomplete measurements: Wrong fit, inconsistent sizing across the run · Pre-shipment inspection, customer returns
• No tolerances specified: Factory's "acceptable" differs from yours; every borderline unit becomes an argument · Inspection disputes, rework costs
• Vague artwork or logo placement: Misaligned prints, crooked embroidery, off-center branding · Visual inspection, retail rejection
• No grading rules: Sizes that don't scale; L fits like M · Fit complaints, size-run failures
• Unclear material references: Substituted fabrics or components that look similar but perform differently · Lab testing failures, durability complaints
• Missing construction details: Wrong seams, weak joints, products that fall apart · Durability testing, warranty claims
• No packaging specs: Damaged goods, crushed retail boxes, missing barcodes · Arrival condition, retail fines
• Outdated revision history: Factory builds from an old version; entire run is wrong · Catastrophic: full-production scrap or rework

Every blank in the document is a decision delegated to the production floor.

How to control revisions without losing control

A tech pack is a living document between the first sample and mass production, and that's exactly when version chaos strikes.

Number every version and date it. "Final_v2_reallyfinal.pdf" is how factories end up cutting the wrong file. Use sequential revision numbers: Rev 01, Rev 02. The number only moves forward.

Send PDFs, keep the editable master. Send the factory a locked PDF so nobody edits the document accidentally mid-production. Keep your editable file for your own revisions.

Require written approval on both sides for every revision. A WeChat message saying "ok make the pocket bigger" is not a revision. The revision is the updated tech pack, re-sent, re-numbered, with both sides confirming the new version supersedes the old. Five minutes of process prevents the most common production disaster: the factory building a change you mentioned but never formally approved, or missing one you thought was obvious.

Tie the revision log to the pre-production sample. Before mass production, the factory produces a pre-production sample from the current tech pack, approved against a specific revision number. If production deviates from the sample, the revision log tells you whether the deviation was authorized. This is the same discipline behind golden samples: a physical reference plus a documented revision, each confirming the other.

Ask the factory's preferred format before you start. Some factories have their own tech pack templates. Asking costs one message and can save weeks of reformatting, and the factory's template tells you what that factory considers important.

Frequently asked questions

Do I need a finished tech pack before contacting a manufacturer?

For OEM factories that build exactly to your specification, yes: a finished tech pack is the price of admission, and the quote you get depends on its completeness. For ODM or development-capable factories, no: they can build the specification with you from reference products or sketches. Match your documentation level to the factory type rather than paying someone to write a tech pack a development factory would have written with you.

What's the difference between a tech pack and a spec sheet?

A spec sheet is one section of a tech pack: the measurements and material specs. A tech pack is the whole package, including sketches, construction, artwork, packaging, QC standards, and revision control. A factory that asks for a tech pack and receives only a spec sheet will come back with questions about everything else.

Can I make a tech pack myself, or do I need a designer?

You can build one yourself with spreadsheet and illustration software if you're precise and willing to learn the conventions. The risk isn't the tools; it's the sections you skip because you didn't know factories needed them. Many first-time importers hire a technical designer for the first tech pack, study the result, then handle revisions themselves.

How detailed should the construction section be?

Detailed enough that a competent factory needs no clarification calls. Specify seam types, stitch density, assembly order, and finishes. If you're unsure what the right construction is, study a reference product in the same category and document how it's built. Vague notes ("high quality stitching") contain no instruction.

Should the tech pack include pricing or cost targets?

Keep target costs in your internal documents, not in the tech pack you send the factory. The tech pack describes what to build; cost negotiation happens against that description. Putting your target price in the instruction document anchors the negotiation against you.

How do I know my tech pack is complete enough to send?

Run the blank test. Read every section and mark anything that says TBD, "to confirm," or relies on a word like "standard," "normal," or "high quality." Each mark is a decision the factory will make without you. A tech pack with zero marks is ready.

The factory-ready test

A tech pack earns its keep in two moments: the day the factory quotes from it and the day production starts from it. Between those two days, the document is the only thing standing between your design and someone else's interpretation of it.

Before you send yours, do one last exercise. Hand the tech pack to someone who knows nothing about the product and ask them to describe exactly what the factory will build: materials, dimensions, colors, construction, packaging. Every hesitation, every "I assume," every question they ask is a gap the factory will fill with a guess. Close the gaps, number the revision, send the PDF, and require the approval in writing.

That's the whole discipline. But the importers who ship consistent product year after year aren't the ones with the best designs. They're the ones whose factories never have to guess.

If you're staring at a design idea and the gap between it and a manufacturer-ready tech pack looks wide, that's exactly the gap a sourcing partner closes. CN Ally's product development service turns concepts into complete specification documents, matches them with vetted factories, and manages sampling and QC against the approved tech pack. Write to hi@cnally.com with your product idea and timeline for a straight answer on what the development path looks like.