Inbox shield
Inbox shield additionally blocks unsubscribed mailing lists from reaching your inbox.
How it works
For a variety of reasons it can happen that after unsubscribing, mails are still being received from a mailing list. Inbox shield additionally blocks all emails from mailing lists that you have unsubscribed from (with Unsubscribe for Gmail) by using Gmail filters.
It does this by matching specific email headers which are linked to that specific mailing list. Inbox shield will not block all the emails coming from the same domain, e.g. @example.com. This means you don't have to worry about missing important emails from the same domain.
Mails that are blocked by Inbox shield are treated according to your Label & Blocklist settings.