Why listing content decides returns
A container is bought on numbers. The end customer cannot hold it, so they read the size, the capacity and the material and imagine their fridge, their shelf or their lunch. If any of those numbers is ambiguous, the product that arrives is a different product from the one they pictured, and it comes back as too small, does not fit or not as described. For marketplace sellers and DTC brands, the listing is part of the specification, and it deserves the same care as the drawing.
The good news is that most of the facts a listing needs already exist in the cut sheet from the partner plant. The work is to carry them across accurately and to say what each number means.
The spec block every listing should carry
| Spec | What to state | Source |
|---|---|---|
| Outer size | L x W x H in mm and inches, labelled outer | Cut sheet, checked on sample |
| Inner size | Usable inside size for storage boxes | Measured on sample |
| Capacity | ml and oz, with brim-full or fill line stated | Cut sheet, checked by fill test |
| Material per part | Base, lid, seal or insert, each named | Supplier declaration |
| Heat and cold use | Microwave, freezer, dishwasher per supplier marking | Supplier marking and sample test |
| Pack contents | Number of pieces, lids included or not | Packing spec |
| Folded size | For collapsible boxes, the folded height | Measured on sample |
Outer and inner size
For food containers, the outer size is the number buyers compare. The reference 750 ml PP box from a partner plant in Guangdong measures 170x115x51 mm outside, and that is what a listing should state, labelled as outer. For storage boxes, the inner size matters more, because the customer is fitting shoes, clothes or files inside. Public listing references put the inner size of collapsible boxes about 2-4 cm smaller than the outer size; a 30 L folding box at about 440x330x230 mm outside will not hold an item that is 440 mm long. A clear folding shoe box at 330x230x140 mm suits shoes up to about 31 cm long and 13 cm high, and saying so in plain words prevents most fit complaints. See shoe and clothes storage boxes.
Give both metric and imperial units, and round in one direction consistently. Converting 315 mm to 12.4 inches and then to 12 inches in the title is how a fridge bin acquires two different sizes on one page.
Capacity and the fill line
Capacity on a cut sheet is usually brim-full. A customer filling a soup cup or a meal prep box works to a lower fill line. State which one the listing uses, and if the number is brim-full, say so. For vacuum containers and pet food bins, capacity is especially slippery: a 20 lb pet food bin holds 20 lb of a particular kibble shape, and public listings themselves note that capacity varies with the food. Say the capacity in litres or quarts and give the weight figure as a guide, not a promise.
Material: name every part
A listing that says plastic tells the customer nothing, and a listing that says BPA-free and nothing else hides the information they need. Name the material of each part: PP base, PP lid, silicone seal; PET bin with PP handle; kraft box with a PET window. Material wording should follow the supplier declaration, for example made with food contact grade PP per supplier declaration. Keep to the facts in the document file:
- Do not write that the FDA has signed off a container. FDA does not approve finished containers; the accurate wording is compliant with 21 CFR per supplier declaration or test report.
- Do not describe PVC as a food container material. In this range PVC appears only in non-heated packaging and storage such as clear folding boxes and gift box windows.
- Do not write biodegradable or compostable on starch-based items unless the exact item is certified to EN 13432 or ASTM D6400, and qualify the claim as the FTC Green Guides require.
- Do not make absolute leak claims. Say leak-resistant in a standard tilt test, and only if the test was run on that model.
The container materials page sets out the honest wording for each resin.
Heat, cold and cleaning
Microwave, freezer and dishwasher statements are the most checked claims on a container listing, and the most often wrong. Copy them from the supplier marking on the item, including the condition: microwave use per supplier marking, lid removed where marked. A partner plant's soup cups carry the PP code 5 and a microwave marking molded into the base; that marking, and a heating test on the sample, are what the listing statement rests on. If no marking exists for a use, leave the use out.
Images and pack contents
Images should show the product at a scale a customer can read: next to a common object, with a size callout, or in a fridge shelf. Show the lid on and off, and the folded state for collapsible items. State the pack contents in words as well as in the image: eight bins, lids not included, is clearer than a photo of eight bins with lids from another set. Avoid any image that shows people's faces or third-party designs.
Keeping listings and production in step
- Write the spec block from the cut sheet before the order is confirmed.
- Check every number on the approved sample and the golden sample.
- Add the spec block to the inspection checklist so each lot is measured against it.
- Update the listing when the plant, the material or the mold changes, not later.
Marketplace sellers will find packing and document requirements for multi-SKU programs on marketplace sellers, and the inspection side on quality control. Typical starting quantities are a few mixed cartons from stock and 1,000-3,000 pieces per item for storage lines, confirmed in writing per program; see MOQ and lead time or send your SKU list through the quote form.