What does the separator correspond to in the product ID of the feed?

The separator separates the product ID from its combination ID when each combination is exported as a separate item in the Merchant Center feed.

For example, in 3-4, 3 is the product ID, - is the separator and 4 is the combination ID. In the simplified example BT3v4, the separator is v.

The full format may also include a prefix and an ISO segment. Always compare the complete feed ID with items[].id in the tag; checking the separator alone is insufficient.

In Dynamic remarketing, under About your Merchant Center data feed, the setting is called What separator do you use between the product ID and the attribute ID? It applies when you export each combination as a separate product.

The module includes retrieval of the separator configured in BusinessTech’s Google Merchant Center module or its Pro version. Check the resulting IDs against your actual feed, especially after an update or a change in ID format.

If you use another export system, entering its separator alone does not establish that the IDs will match: the product and combination-change paths use only the product ID when no BusinessTech Merchant Center module is detected. Have this setup checked before relying on combination-level tracking.

See also product ID prefixes, combination-level remarketing and testing the tag.

Merchant Center feed settings: product ID prefix and combination separator.