Why does eBay reject my size even though it is a real size?

Because it is not a size for the Size Type and Department you picked. Set Department to Men and Size Type to Big & Tall before trying 4XL, and the value is accepted.

Should I write the measurements in the size field?

No. "4XL Waist 111 cm" is not a value eBay accepts. Put 4XL in the size field and the measurements in the description, where a buyer reads them anyway.

Is Brand required if the item has no brand?

Enter "Unbranded". Leaving it empty can fail the listing, and an empty brand hides you from filters that include unbranded goods.

Guides 7 min readUpdated 25 September 2026

eBay item specifics for clothing and shoes

Item specifics are the structured fields under an eBay listing: brand, colour, size, material, department. Buyers filter by them, so a listing that leaves them out is not merely untidy — it is missing from the results the buyer is actually looking at.

Clothing and footwear are the categories where this bites hardest, because eBay does not accept a free-typed size. It accepts a size from the list that belongs to the Size Type and Department you chose, and it changes those lists as categories change.

Why a size eBay will not accept is the commonest reason a listing fails

On AliExpress a size is whatever the seller typed: "XXL", "US 9.5", "4XL Waist 111 cm", "Asian size L (fits UK 8)". eBay expects a value from its own list for that category.

Paste the AliExpress value straight in and eBay either rejects the listing or accepts a variation nobody can filter to. The fix is a translation, not a retype: XXL becomes 2XL, XXXL becomes 3XL, and an Asian size has to be mapped to the size the buyer in that market understands.

What AliExpress says	What eBay expects	Why
XXL	2XL	eBay lists the doubled sizes numerically
XXXXL	4XL	Same rule, further along
US 9.5	9.5	The market is already set by the site you are listing on
4XL Waist 111 cm	4XL	The measurement belongs in the description, not the size field

Size Type and Department come first

These two decide everything else. Department is who the garment is for — Men, Women, Boys, Girls, Unisex Adult. Size Type is the cut: Regular, Plus, Big & Tall, Petite, Juniors, Maternity.

Choose them and eBay narrows the allowed sizes to the ones that make sense together. Choose them wrongly and every size you try is refused, which reads as a size problem when it is really a Department problem.

A men’s 4XL is a Big & Tall size, not a Regular one. That single mismatch rejects more clothing listings than any other.

Which specifics eBay actually requires

eBay marks some as required and some as recommended, and the marking differs by category. As a rule, for clothing and footwear expect to need:

Brand — "Unbranded" is a valid answer and better than leaving it empty
Department — who it is for
Size Type — the cut
Size — from eBay’s list for that Size Type and Department
Colour — the main one, not a list of every variation
Style, Material, Occasion — recommended, and they earn their place in search
US Shoe Size and Shoe Width for footwear, which are separate fields

The fields worth leaving out

AliExpress product data carries fields that mean nothing on eBay and look like noise to a buyer: internal size tables as raw text, shipping claims that contradict your own postage, supplier stock codes.

A listing tool that copies everything across is not doing you a favour. What you want is the fields eBay asks for, filled from the source, with the rest left where it was.

How to do this without typing it a hundred times

eBay publishes, per category, which specifics it wants and which values it accepts. That list can be read by software, which means the translation from an AliExpress size to an eBay one can be done once and reused.

eBay Lister asks eBay for the category’s own list, matches each AliExpress variation against it, and shows you what it could not match so you can decide. Sizes it knows the rule for — XXL to 2XL and the rest — it converts on its own.

Questions

Why does eBay reject my size even though it is a real size?: Because it is not a size for the Size Type and Department you picked. Set Department to Men and Size Type to Big & Tall before trying 4XL, and the value is accepted.
Should I write the measurements in the size field?: No. "4XL Waist 111 cm" is not a value eBay accepts. Put 4XL in the size field and the measurements in the description, where a buyer reads them anyway.
Is Brand required if the item has no brand?: Enter "Unbranded". Leaving it empty can fail the listing, and an empty brand hides you from filters that include unbranded goods.