This card gives a detailed view of a Gmail conversation, without you having to go to Gmail, it's only visible for users who are connected to Google Apps. You get to the view by clicking "Show more" from any of the Google Apps Cue cards.
If you wish to get to the thread in Gmail - hover the red bar and click “Open in Gmail” and Brisk will open it up in Gmail for you. The bar to the right will stay grey until you’ve logged the conversation to Salesforce, when you’ve logged the conversation the bar turns blue.
If you haven't logged an email the “Log emails” button will show up. It helps you to log a conversation with one click. The email is logged to the related Salesforce record.
The tab named “Participants” indicates how many participants that are part of the conversation, and helps you to add people to Salesforce as a lead or contact. In this case, the person is already logged and you can go to the lead view by clicking the name of the people that are listed. The “Conversation” tab indicates the number of emails that has been sent in the specific thread and gives you a snippet with the beginning of every reply.