3. Google Product Ads/Extension

Google product Ads/Extension is a way for you to enrich your existing ads with more relevant and specific information about your retail merchandise. Product extensions allow you to use your existing Google Merchant Center account to highlight your products directly in your search ads.

When your ad appears and your Google Merchant Center account contains products that are relevant to the user's query, product extensions will show the images, titles, description and prices of your products in a plusbox under your ad.  In fact brands can promote their entire product inventory through paid search and in theory, generate more qualified clicks because Google providing the user with more product information up front.