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How can I get my listings to display the Unit Info?
NOTE - UnitInfo is not supported in sandbox
This article will give you the information necessary to get Unit Info displayed on a listing
UnitInfo - Contains information about the weight, volume or other quantity measurement of a listed item. The European Union requires listings for certain types of products to include the price per unit so buyers can accurately compare prices. eBay uses the UnitInfo data and the item's listed price to calculate and display the per-unit price on eBay EU sites.
Note: This information is currently required only for EU business sellers, and only for listings with a Buy It Now option.
Here is a screen shot of a listing that contains unit info,
The unit info is enabled for EU sites and only for BIN (buy it now) items. Also we disable it for MSKU items. So the actual UnitInfo container does not need to be added when using the API. What we look for on our end is key item specifics to tell us the UnitQuantity and UnitType. In the example given in the screen shot the item specifics are,
<Name>Anzahl der Einheiten</Name>
In ViewItem page, we take the BIN price (in this case 35.90) and divide it by UnitQuantity value (in this case 0.7) and then append the Unit type (L) with it. You will see an actual UnitInfo container in the GetItem API, but that container cannot be used for the add item requests. We look for item specifics.