How are fields with product codes from 1C stored in Bitrix?

Question

1C-Bitrix

Good afternoon everyone.
Tell me, how is the integration of goods into Bitrix from 1C? Where and how are 1C codes for binding stored? Or does it happen in some other way?
In UMI, for example, there is a correspondence table for store product-> product from 1C.

Answer 1

External code. The field of the XML_ID element.

Answer 2

Binding codes can be viewed by first enabling the option in the "Information blocks" module settings - "Show download code from external sources".