How to use page-sets?

[yves]

In the "Administration" section there's a value "Page links" with the following description: "Number of 'number' links use for page-sets"

 

I presume this means that I can add a tag to the "Product description" text field as to specify where I would like a new page to start.

 

I can't find any info on this topic, nor do I know what this presumed tag would be.

Since the documentation for OSC is completely absent, accept for the very basic KB and this forum, I sincerely hope somebody knows the answer to my question.