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The “Custom Label” field in is an optional field in several eBay seller tools.
The “Custom Label” field in Turbo Lister, File Exchange, Selling Manager and Selling Manager Pro maps to the Item.SKU element in the GetItem call.
eBay selling tools Turbo Lister, File Exchange, Selling Manager, and Selling Manager Pro define a “Custom Label” field.
Turbo Lister defines the “Custom Label” field as follows :
Turbo Lister Custom Label is a seller-defined item identifier. Sellers can enter any information in the Custom Label field that identifies an item. Unlike Turbo Lister’s former Item Label functionality, where the data stayed within Turbo Lister, the Custom Label data can now be transferred into Selling Manager, Selling Manager Pro, and File Exchange applications. This new feature will also help sellers track and manage their listings.
If you wish to track this “Custom Label” field through the GetItem call, you will need to track the Item.SKU field which has this description in the GetItem documentation :
This element is a SKU (stock-keeping unit) defined by a seller. The seller can use a SKU to identify one item or use the same SKU for multiple items. Preferable to ApplicationData for SKUs and inventory tracking. Different sellers can use the same SKUs. This element can be used by sellers to track complex flows of products and information. This element preserves a SKU, enabling a seller to obtain it before and after a transaction is created. To remove a SKU when you revise or relist an item, use DeletedField. Not applicable to Half.com. Max length: 50.
Turbo Lister : http://pages.ebay.com/turbo_lister/
File Exchange : http://pages.ebay.com/file_exchange/
Selling Manager : http://pages.ebay.com/selling_manager/
Selling Manager Pro : http://pages.ebay.com/selling_manager_pro/
GetItem API call : http://developer.ebay.com/DevZone/XML/docs/Reference/eBay/GetItem.html