The Email Events is used to get information about events generated by emails or email campaigns sent through a HubSpot account to CRM recipients.
HubSpot default fields :
AppId
AppName
Attempt
Bcc
Category
Cc
Created
DeviceType
DropMessage
DropReason
Duration
EmailCampaignGroupId
EmailCampaignId
FilteredEvent
LinkId
PortalId
PortalSubscriptionStatus
Recipient
Referer
ReplyTo
Response
SmtpId
Source
SourceId
Status
Subject
Subscriptions
Type
Url
UserAgent
Browser_name
Browser_family
Browser_producer
Browser_producerUrl
Browser_type
Browser_url
Browser_version
Location_country
Location_city
Location_state
Location_zipcode
SentBy_id
SentBy_created
Links :
HubSpot Email Events API Documentation