How do you inspect a first production run before it ships?

Have the factory test every unit, and have an independent, third-party inspector check a random sample twice, using AQL sampling. For a first run of about 1,000 units, book a during-production inspection (DUPRO) when 20 to 30% of the units are built, so a problem in the process can still be fixed, and a pre-shipment inspection (PSI) once the whole order is produced and at least 80% is packed, which is the one to tie your final payment, the balance due after the deposit, to. The pre-shipment inspector pulls a random sample, 80 units from a lot (the batch being inspected) of 1,000 under the usual sampling standard (ISO 2859-1, the same tables as ANSI/ASQ Z1.4), and checks it against your golden sample, the approved unit production is checked against, and a written checklist: looks, function, firmware version, battery charge, labels and packaging. A sample catches problems that repeat across the run, but it can easily miss a rare fault in one unit, so electrical and safety checks have to run on every unit at the end of the factory's line, and the inspector should confirm that those per-unit test records exist.

What are the inspection stages, and which does a first run need?

The table lists the usual stages, when each happens, what it catches, and whether a first run of about 1,000 units needs it.

Stage	When	What it catches	For a first run of about 1,000 units
Incoming parts check	When parts arrive at the factory	Wrong or counterfeit parts, the wrong board revision, bad battery cells, the wrong plastic color	The factory's job; ask what it checks on battery cells and the main chips, and for the records
First-article inspection (FAI)	The first units off the real line	Setup mistakes before they repeat a thousand times; differences from the golden sample, drawings and parts list	Yes; often combined with the early check below
During-production inspection (DUPRO)	When about 20 to 30% of units are built (firms quote anything from 20 to 50%)	Problems that repeat across the run, while there's still time to fix the rest	Recommended, because nothing about the line is proven yet
Pre-shipment inspection (PSI)	When the whole order is produced and at least 80% is packed	A final random sample across the whole lot: looks, function, labels, packaging, quantity	The minimum; tie the balance payment to it
Loading check	While cartons are loaded	Wrong carton counts, mixed products, swapped cartons, a damaged container	Usually skipped for a few pallets; ask the pre-shipment inspector to count cartons, photograph the carton marks and seal sample cartons

What does AQL mean, and how many units get checked?

Inspection firms use the sampling tables in ISO 2859-1 and ANSI/ASQ Z1.4, which share the same numbers. The lot size sets the sample size: at general inspection level II, the usual default, a lot of 501 to 1,200 units gets an 80-unit sample and a lot of 1,201 to 3,200 units gets 125.

The AQL (acceptance quality limit) sets how many defective units the sample may contain. A common setting for consumer products is critical 0, major 2.5 and minor 4.0:

• For an 80-unit sample: no critical defects; up to 5 units with major defects (6 fails the lot); up to 7 with minor defects (8 fails).
• For a 125-unit sample: no critical defects; up to 7 majors (8 fails); up to 10 minors (11 fails).

Count defective units, not defects: a unit with three scratches counts once, and a unit with a major and a minor defect counts as a major. "Critical 0" is a buyer's rule rather than a column in the standard, so write the exact plan into your purchase order.

What AQL 2.5 doesn't mean. It isn't "2.5% of the lot may be defective," and passing doesn't prove the lot is that good. Working the odds for a 1,000-unit lot at AQL 2.5: a lot where 1 unit in 20 has a major defect still passes about 4 times in 5, and one where 7% are defective passes about half the time. If 1% of units have a critical defect, such as a pinched battery wire, an 80-unit sample finds one only a little over half the time. The sampling tables were designed for a steady stream of lots from one supplier, and a first run is a single lot, so a pass tells you less than it seems; anything safety-related has to be tested on every unit.

What goes on the checklist for an electronic product?

A checklist has three kinds of items: specifications to confirm (yes or no), defects to look for and classify on every sampled unit, and tests with a stated number of units.

Write down how to look. One published supplier standard for plastic parts sets the light at about 860 to 1,290 lux, the viewing distance at 15 to 18 inches, and 2 to 10 seconds per surface depending on its size, with surfaces graded A (most visible) to D (hidden). Other standards agree on about 18 inches for the main face but differ on time and light, so pick one, write it into the checklist, and agree it with the factory before production. Limit samples, the physical examples of the worst acceptable defect, settle borderline cases.

What to check on each sampled unit:

• Quantity: units packed against the order.
• Appearance: each surface against its class; color against the golden sample; the gap between the case halves; the logo print.
• Assembly: no rattles or loose parts, screws present, buttons feel right, no pinched wires.
• Function: power on, every button, the lights or display, charging, wireless pairing, sensor readings.
• Firmware: the version read from the unit matches the release named in the purchase order.
• Battery: charge at the agreed level, the unit in its shipping mode, no swelling, and the battery model matching its UN 38.3 test summary.
• Labels and serial numbers: regulatory marks, the FCC ID if the product has a radio, a readable serial number that matches the box.
• Barcodes: the product and carton barcodes scan and decode to the right numbers.
• Packaging: inserts, manual, cable and accessories present; printing matches the artwork.
• Cartons: shipping marks, including the country of origin, the number of units per carton and the weights.
• Drop tests: a few units and a few cartons, then a function check of what was dropped.

Defect classes. Critical means it could hurt someone or break the law, such as a short circuit or a swollen battery. Major means most buyers wouldn't accept it: a dead unit, a button that doesn't work, the wrong firmware, a barcode that won't scan. Minor means most buyers wouldn't mind, such as a small mark on a hidden surface. Don't file everything you dislike under critical: one critical defect fails the whole lot.

Is factory QC enough, or do you need a third-party inspector?

You need both. The factory's quality (QC) team reports to the factory; an independent inspector reports to you. The two do different jobs:

• The factory tests every unit. A board test on a fixture of spring pins (pogo pins) that touch test points checks each assembled board, power, startup, sensors, radio and every input and output, often in 20 to 40 seconds a board, logged by serial number. A final test then checks each finished unit in its case: buttons, display, charging, pairing. Together they catch faults in single units, such as a bad solder joint, that a sample would almost always miss.
• The inspector samples to verify. On the sampled units, the inspector reruns a function check, reads the firmware version, and checks that the factory's test log has those serial numbers. Ask the factory for the run's yield and its top failure causes too.
• Firmware. Give the factory the release file name and its checksum in writing, have the end-of-line test read the version back and log it, and write the firmware check into the inspection plan as a zero-acceptance item, so a wrong version on any sampled unit fails the lot, because it's almost always the whole batch. Check the log for duplicate serial numbers or network addresses across the run, not just in the sample.
• Burn-in. Running units powered for hours catches early failures, not assembly mistakes. On a first run of about 1,000, a short powered soak on a sample or the first batch is common; burning in every unit is rare unless the pilot build showed early failures.
• Battery charge for shipping. Since January 1, 2026, air rules require 30% charge or less for lithium-ion batteries packed with a device (above 2.7 Wh), and recommend it for batteries built into one. Agree a target of about 30% and a low-power shipping mode, so units travel safely and don't arrive flat after weeks in transit, and have the inspector check both. Function and charging checks wake the sampled units and raise their charge, so have them set back to shipping mode and charge before they're repacked.

How much does a third-party inspection cost?

Inspection firms charge by the inspector-day. A pre-shipment inspection of a single product at 80 to 125 samples takes a day for simple goods, but often two for an electronic product with a full function test on every sampled unit. One firm lists $280 a day for most of Asia, including China with travel, and $380 for Taiwan and South Korea; guides put China at roughly $200 to $400. We found no published day rates for the US or Mexico; expect more, often plus travel, and ask two or three firms. A re-inspection usually costs the same as an inspection.

You book and pay the inspection firm, and send it your checklist, photos of the golden sample, the product specification and the factory's contact. Book as soon as the order is confirmed, then confirm the date with the factory a few days ahead. The factory needs at least 80% of the order packed, plus power, test fixtures and a table for the inspector; an inspector who arrives to find the goods not ready is usually still charged. The report gives a pass or fail, the sampling plan, defect counts by class, and photos and videos, usually within a day or two.

What happens if a lot fails inspection?

• Sort and rework at the factory. The most common outcome: the factory checks every unit for the failed defect and fixes or replaces the bad ones, often within days.
• Re-inspect. Usually one more day after rework.
• Accept with a discount. Possible for goods that still sell, but risky for a first run under your own brand.
• Refuse and have the run remade. For defects that are widespread and can't be fixed.
• Ship anyway. You lose your leverage: once the goods leave, sending them back is impractical, and an unpaid factory is the one most willing to fix things.

Write these into the purchase order before production:

• the inspection standard and plan, for example "ISO 2859-1, single sampling, normal, general level II; critical 0, major 2.5, minor 4.0", along with the checklist and the golden sample;
• your right to send an inspector at named stages, and that the factory provides power, fixtures and space;
• that the balance is paid after a passed pre-shipment inspection, or your written waiver;
• that if a lot fails, the factory sorts and reworks at its own cost within an agreed number of days and pays for the re-inspection, or it comes off the balance;
• that units removed in sorting are replaced, so the shipped quantity matches the order;
• that only passed, sealed cartons are loaded.

Who keeps the golden sample, and how changes reach every supplier, is covered in What falls between suppliers in a first production run; the inspection terms to look for in a quote, in What's actually in a production quote.

Example: 1,000 desk lamps

This is an illustration, not a customer project. The product and all the numbers are made up.

A team's first run is 1,000 desk lamps with a USB-C port and a small battery.

• Early check, at 250 units built: the inspector samples 32 units, the sample size for a batch of 250, and finds 3 with a loose USB-C port. A fixture is holding the board slightly crooked. The factory fixes the fixture and reworks the 250 units before going on.
• Pre-shipment inspection, at 900 packed: 80 units sampled. No critical defects, 6 units with a sticky button (major) and 5 with small marks on the base (minor). Six majors fails the lot; five or fewer would have passed.
• Rework: the purchase order says the factory sorts and reworks at its own cost within five days and pays for the re-inspection. It checks every button, replaces 41 caps, and the re-inspection passes with 1 major and 3 minors. The firmware version and battery charge, about 30%, matched on every sampled unit both times.
• Cost: in this made-up example, four inspector-days (one for the early check, two for the pre-shipment inspection, one for the re-inspection) at $350 cost $1,400, of which the factory pays $350 for the re-inspection under the purchase order. The balance is released after the passed report.

Where we come in

If you're planning a first run and want inspection built in from the start, this is one of the situations Anamor takes on. We produce, inspect, pack and ship: you get the first assembled units with the first-article inspection report, then inspection results for each lot, and units at your warehouse.

Anamor takes US hardware teams with a working prototype into their first production run: we redesign the product for production, line up partner factories and suppliers in the US and overseas, price it at your quantities, and run the build through to shipping.

Send what you have: photos of the prototype, CAD if you have it, the parts list, and how many you plan to make. Need an NDA? We'll send our mutual NDA, or review yours, before you send files. Within two business days, a real person on our team will reply with a free first look at your production run and a few times to talk.

Frequently asked questions

What is a pre-shipment inspection, and when should it happen?

A pre-shipment inspection is an independent check of a random sample of the finished order, against your golden sample and checklist, before it leaves the factory. Book it once the whole order is produced and at least 80% is packed, and tie the balance payment to a passed report. For a first run, add an earlier check at 20 to 30% built.

What does AQL 2.5 mean in a product inspection?

AQL (acceptance quality limit) 2.5 is the setting usually used for major defects. For an 80-unit sample, drawn from a lot of 501 to 1,200 units, it accepts up to 5 units with major defects and fails the lot at 6. It doesn't mean 2.5% of the lot may be defective; a lot with 5% defective units usually still passes.

How much does a third-party inspection cost?

Inspection firms charge per inspector-day. A pre-shipment inspection of one product takes a day for simple goods and often two for an electronic product with full function tests. In China, expect roughly $200 to $400 a day; Taiwan and South Korea run higher, and the US or Mexico more again, often plus travel. A re-inspection usually costs the same.