The Click‐to‐Call product can support up to 10 optional data fields which are used to hold contextual information for a call. This can include information derived from the call template and also information gleaned from the visitor’s session on the customer’s site.

These 10 fields have system‐wide internal names of var1 to var10. Each customer account can define their own names or labels for these fields.

Default information for some of the fields is provided automatically from the call template. This can be overridden by information derived from the visitor session. To pass information from the visitor session, you simply need to define the JSON variables and values accordingly.

The optional data fields can be identified using their customer‐specific labels for these fields or using the system‐wide internal names. For example, to set the value of the third optional data field to XYZ54321, where its customer‐specific label is ‘CustRef’, and the default name is ‘var3’, then this can be done in either of the following two ways, using JSON notation: