Set the additional postback similar to the standard postback settings.

Also, one additional postback can be set in the campaign settings.

! If you set a postback both in the campaign settings and in the source settings, the tracker will send both postbacks.

In the source settings, find the section for additional postback settings:

In the opened settings, find the Criteria section:

When adding a criterion, the following window will appear:

Adding and configuring the criteria for sending a postback is similar to configuring redirection rules.