Tech pack: the spec document that protects your reorders
A tech pack is the spec document that keeps reorders identical to run one. The anatomy, the version-control habit, and a one-page version for non-apparel.
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The first production run gets all the attention; the second run is where brands get burned. The reorder comes back subtly wrong — a strap narrower, a plating duller, a label two millimeters low — and nobody can say what the factory was actually told, because the answer lives in a year-old email thread. A tech pack is the fix: the dated, versioned spec document your factory produces against, so the reorder is boring. Same spec, same factory, same result. Here's what goes inside one, why the reorder angle matters more than the first-run angle, and a one-page version for products that don't wear.
What a tech pack is
The term comes from apparel, so start with the neutral baseline. Per Techpacker, a fashion-manufacturing tool (accessed October 2026): "A tech pack is a structured specification document that gives a clothing manufacturer every instruction needed to produce a garment accurately."
Strip out "clothing" and "garment" and the definition generalizes to anything another company produces to your design: dog harnesses, enamel pins, ceramic planters, phone stands. The tech pack is the operational sibling of your contract — the contract says who owns what and who pays for what (the clauses that matter there are a subject of their own), while the tech pack says what the thing physically is. It is also the difference between a factory quoting a price and a factory guessing one.
What goes inside: the anatomy
A full apparel tech pack runs seven sections. Each exists because some amount of ambiguity had to be removed from the production line:
| Section | What it contains | Why the factory needs it |
|---|---|---|
| Measurement spec sheet | Key dimensions with tolerances (±2mm, ±0.2mm) | "Close enough" isn't enforceable; tolerances are |
| Materials / BOM | Every material with weight, finish, and supplier references | Locks the inputs, not just the outcome |
| Construction / callouts | Stitch types, seam finishes, assembly order, close-up diagrams | Removes interpretation from the line |
| Grading rules | How measurements scale across sizes | One base spec governs every size you sell |
| Colorways | Colors with codes — Pantone, hex, dye references | "Forest green" is five different colors |
| Packaging + labeling | Polybag, box, inserts, care labels, barcode placement | What ships is part of the product |
| Artwork placement | Logo files, print positions, exact dimensions | Protects the brand surface people actually see |
Notice what the table is really saying: every row converts a conversation into a number or a file. A spec that says "webbing: 25mm nylon" plus a tolerance is enforceable; a spec that says "same webbing as before" is a memory test.
Why the factory builds exactly what's written
A factory quotes and produces exactly what's specified — nothing else is enforceable. This isn't cynicism; it's how the economics work. The quotation is priced against the document, so any change to the document is a change order with a new price, and anything outside the document is, from the factory's side, free territory. If the drawing doesn't state a stitch density, the line uses whatever it used last week.
That's also why vague specs produce surprise quotes. A factory that can't tell if "durable" means 800D or 1680D nylon will price the safer guess, quote a range, or come back later with an adjustment. The tech pack is what lets a factory commit to a number — and lets you hold them to it.
The reorder angle: version control for your product
Here's the part most tech pack explainers skip, and it's the one that matters most to a merchant: reorders.
A reorder should be the least interesting order you place all year. The product was designed once; the factory made it once; the second run should be an act of repetition. Spec drift creeps in when the spec itself has no home — when it lives in email threads, when the person who briefed the first run has left, when last season's remaining sample is the only physical record and it's been on a shelf, stretched, for a year.
The defense is boring and it works:
- Date every version. v1 for the first run. When a change is approved — a wider strap, a new zipper — that becomes v2, dated, with the change noted. The factory works from the latest PDF, not from anyone's memory.
- Reference the version on the PO. "Per tech pack v2, dated March 3" on the purchase order closes the loop between your paper and theirs.
- File the spec that produced the golden sample. When you approve a golden sample from the first run, keep the exact spec version that produced it together with the sample. The pair — sample plus spec — is your evidence for every reorder argument you'll ever need to have. The sampling process itself, from first prototype to golden sample, is covered in how to order product samples.
- Check the reorder against both. When the reorder lands, incoming inspection compares what arrived against the spec and the golden sample — not against last season's memory. The item-by-item checks live in the quality-control inspection checklist.
Do this and the tech pack stops being a first-run design document and becomes what it really is: version control for your product.
When there's no tech pack: a harness reorder gone sideways
A worked example, labeled illustrative because the numbers are representative rather than real:
A brand runs 1,200 dog harnesses in March. The spec — such as it is — lives in a thread of 43 emails. The straps were 25mm webbing; everyone who was on that thread remembers it. In September, the reorder arrives and the webbing measures 15mm. The factory's production manager, sorting materials for a different client, had 15mm webbing on hand and, in his words, "improved" the design to use it. Nobody is lying. Nobody can point to a document either, because the document never existed. The sample from the first run sold at a trade show in June. The brand's options are a discounted clearance channel or a rework bill — and the factory, politely, notes that no spec ever said 25mm.
The loss isn't just the units. It's every hour of the argument, and the relationship damage that comes from having an argument with no referee. Ten rows in a table would have ended the conversation in one message.
Who owns the document
You do — or your designer does, working to your brief. The factory never owns it.
Plenty of factories will draft a tech pack as a paid service, and a good one is worth the fee. But the file, the versions, and the golden-sample record live on your side, in storage you control. If the factory is the only custodian of your product's definition, then switching factories means starting from zero: the new factory quotes from a photocopy of a sample and the negotiation starts over. Ownership of the spec is also what separates the manufacturers from the middlemen when you're choosing a partner — the questions that sort that out are in how to find a manufacturer, and the branding arrangement you're buying shapes who writes the spec in the first place, per private label vs white label.
The one-page version for non-apparel goods
Full apparel tech packs can run fifteen pages, and a brand selling coffee beans or enamel pins doesn't need that. What it needs is the discipline at one-page scale: a dated spec sheet with the same five fields, one row each.
| Field | Example entry (illustrative — enamel pin) |
|---|---|
| Dimensions + tolerances | 30mm × 25mm, thickness 1.8mm, tolerance ±0.2mm |
| Materials | Zinc alloy base, hard enamel fill, rubber clutch |
| Finish | Polished gold plating, PMS 871C reference |
| Packaging | Opp bag + backing card, 90mm × 120mm |
| Labeling | Logo and version code on backing card, bottom-right |
Date it, version it, send the PDF with every PO, and re-send it with every reorder — even the tenth one, especially the tenth one. The same discipline carries into outsourced production more broadly: food, beverage, and cosmetics brands running a co-packer keep exactly this kind of spec pack for the facility to produce against, batch after batch. The co-packer relationship guide covers what changes when production leaves your building.
Common questions
What is a tech pack? A structured specification document giving a manufacturer every instruction needed to produce a product accurately — measurements with tolerances, materials, construction, colors, packaging, and labeling, per Techpacker's definition (accessed October 2026). It originated in apparel but applies to any product another company makes to your design.
What does a tech pack include? The core anatomy: a measurement spec sheet with tolerances, a materials/BOM list with supplier references, construction callouts, grading rules, colorways with exact color codes, packaging and labeling specs, and artwork placement files. Each section converts an agreed conversation into a number or a file the factory can be held to.
Do I need a tech pack for reorders of an existing product? Yes — arguably more than for the first run. Reorders fail through spec drift: the spec lives in email threads, staff change, and the factory works from memory. A dated, versioned tech pack referenced on the PO, filed alongside the golden sample it produced, makes the tenth order as predictable as the first.
Who creates a tech pack? You or your designer — never the factory. A factory can draft one as a paid service, but the file, its versions, and the golden-sample record must live in storage you control. If the factory is the only custodian, switching suppliers means rebuilding your product definition from zero.
What's a tech pack for non-apparel products? A one-page spec sheet with five fields: dimensions with tolerances, materials, finish, packaging, and labeling. A dated, versioned PDF sent with every purchase order. It's lighter than an apparel tech pack but enforces the same principle — the factory builds what's written, not what's remembered.
Next step
Pull the PO for your last reorder and try to reconstruct, in one page, what the factory was actually told. If the honest answer is "an email thread, somewhere," write the one-page spec for your best-selling SKU this week, date it v1, and attach it to the next order you place — then check the incoming goods against it using the inspection checklist linked above.