The InboxGeek system will retrieve all of the lists in your SendGrid account. In order for your integration to perform, a list size of at least 30k is recommended. If a list size of under 15k is integrated, it is unlikely to see any results from your integration.
Select the list that you’ve created/chosen to use with InboxGeek and click Next.
NOTE: Multiple lists can be chosen for your integration. InboxGeek will filter and suppress duplicate contacts to prevent sending numerous events to a single contact.
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InboxGeek will move you to the next tab, Integration.