Amazon-Ready Bras: Get FNSKU Labels & Poly Bags Pre-Applied at the Factory

Yes — a bra factory can apply your Amazon FNSKU labels, poly-bag each unit and print the required suffocation warnings during production, so your cartons ship straight into an FBA warehouse without a prep center in between. To make it happen you send the supplier four things before bulk packing: your FNSKU barcode (the X00-prefixed code Amazon generates per listing), poly-bag specs, the exact suffocation-warning wording, and a carton/label plan. Done at the factory, FBA prep stops being a separate cost-and-delay step and becomes part of the production run you already pay for.

An FNSKU (Fulfillment Network Stock Keeping Unit) is the barcode Amazon assigns to each product you send to FBA. It is not your UPC or EAN — it is generated inside Seller Central when you create or convert a listing to 'FBA stickered/labeled by seller,' and it starts with an X followed by ten characters. Amazon will scan this single barcode at receiving, so the factory must print it as a scannable label (the spec is a 1x2 inch / 25x51 mm thermal or laser label, code-128 symbology, with the human-readable FNSKU, the product title and a condition note such as 'New') and place it on the outside of each poly-bagged bra, covering any manufacturer barcode so only one scans.

Poly-bagging is mandatory for soft goods like bras, and Amazon enforces a specific rule that trips up first-time sellers: any poly bag with an opening of 5 inches or greater (measured when laid flat) must carry a suffocation warning. The warning text must be legible and a minimum font size scaled to bag size — Amazon specifies 24-point type for bags 60 inches and over, down to 10-point for bags 29.5 inches and under. The bag must also be transparent, fully seal or have a self-adhesive closure, and the FNSKU label on the bag must remain scannable. A factory that already runs FBA orders bakes all of this into the bagging line rather than leaving you to re-bag 1,000 bras at home.

The standard suffocation warning Amazon accepts reads: 'WARNING: To avoid danger of suffocation, keep this plastic bag away from babies and children. Do not use this bag in cribs, beds, carriages or playpens. This bag is not a toy.' It can be printed directly on the poly bag or applied as a sticker — printing it into the bag artwork is cheaper at volume and looks cleaner for a private-label product. If you sell into the EU or UK as well, ask the factory to add the equivalent multilingual warning and the resin-identification triangle, so the same packed unit is compliant across your marketplaces.

The reason to push prep upstream is money and time. Amazon's FBA label service charges a per-item fee to apply FNSKU labels when you don't, and its bagging/polybagging and 'unbundling' prep services add further per-unit fees — for a 1,000-piece bra order those per-unit charges compound into a meaningful cut of your margin, on top of the receiving delay while Amazon preps the units. US-based prep centers typically charge a per-unit fee plus receiving and storage. Factory prep replaces both: the labor is priced into a low-cost manufacturing region and added to your existing production run, so you pay once and the carton is shelf-ready on arrival.

A factory-prep checklist for an Amazon-ready bra order looks like this. One, finalize the listing and generate the FNSKU in Seller Central, then send the supplier a vector or high-resolution PNG of the barcode plus the X00 string as text (so they can regenerate it cleanly). Two, confirm poly-bag gauge and dimensions — a typical bra fits a 6x9 inch or 8x10 inch bag at 1.5-2 mil thickness; specify clear, self-seal, with the printed suffocation warning. Three, lock the label artwork: FNSKU label content, placement (front, flat, fully visible), and that it overrides the factory's own barcode. Four, agree the carton spec — Amazon's max carton weight is 50 lbs (or up to 100 lbs for a single oversized unit), each box needs an FBA shipment ID and box label, and you'll usually apply those last from your shipment plan.

For private-label sellers, factory prep is also where branding and compliance meet in one pass. In the same production run the factory can sew in your woven brand label and care/content label (US law requires fiber content, country of origin and care instructions on textiles), apply your hangtag, poly-bag the unit, and stick the FNSKU on the outside of the bag. That sequence matters: the brand and care labels go on the garment, the FNSKU goes on the polybag, so the unboxing experience stays branded while Amazon still scans cleanly. Trying to retrofit this at a prep center means opening every bag, which defeats the point.

There are two FNSKU edge cases worth flagging before you commit a bulk run. First, Amazon's 'Ships in Product Packaging' and commingled-inventory options can change whether you sticker at all — confirm your listing is set to 'FBA labeled by seller' so the factory's FNSKU is actually required and used. Second, if you're enrolled in Amazon Transparency, those units need Transparency codes (unique per-unit 'T' barcodes) in addition to or instead of the FNSKU; a factory can apply serialized Transparency labels too, but you must supply the code batch and the placement rules, because each label is unique rather than repeated.

This is where MOQ shapes how realistic factory prep is for a new seller. At a 100-piece minimum per style, you can validate a single bra SKU as fully Amazon-ready — FNSKU-labeled, poly-bagged, warning-printed, brand-labeled — for a first FBA shipment, instead of being forced into a 1,000-3,000-piece run before any factory will customize packaging. That lets you test sell-through on Amazon at low inventory risk, confirm the listing and prep flow work end to end, then reorder the winners at volume with the exact same prep spec already on file.

LXSC is a Foshan-based lingerie and bra factory running OEM, ODM and private-label programs at an MOQ of 100 pieces per style, with seamless, wireless, push-up, strapless, plus-size and sports bras in its catalog. For Amazon sellers, that means FNSKU labeling, poly-bagging with printed suffocation warnings, branded woven and care labels, hangtags and carton labeling can be specified as part of the production order rather than handed to a separate prep center. With worldwide shipping and established trade across Southeast Asia and global B2B markets, the same Amazon-ready spec scales from a 100-piece test shipment into a repeating program.

A practical way to start: build and finalize one bra listing in Seller Central, generate its FNSKU, and request a sample from the factory with the full prep applied — FNSKU on the polybag, suffocation warning printed, your brand and care labels sewn in. Scan-test the FNSKU yourself before bulk, confirm the bag and warning meet your marketplace rules, then release the production order. Once the spec is approved on a sample, every reorder ships carton-ready, and your only remaining step is generating the FBA shipment and box labels from your shipment plan.