Google is experimenting with a variety of AdWords features that can only be enabled by linking your Google Merchant Center Account with your Google AdWords account. This gives AdWords access to your raw inventory data feeds.
If you have a professional Google AdWords management team, we recommend that you have them read this article and enable these features as they see fit.
Log in to your Google AdWords account and write down your "Customer ID" (located in the top right corner of the screen).
Log in to your Google Merchant Center account, click "Settings", click "AdWords", and enter your AdWords Customer ID from step 1. If you are a VersaFeed subscriber, simply email us your AdWords Customer ID and we will add it to your Google Merchant Center Account.
Back to your Google AdWords account, click "Campaigns", click the "Ad extensions" tab. Click the dropdown box labeled "View ....", and change it to "Product Extensions". Click "New Extension" — at this point you can select which campaigns you would like to enable for the product extensions.