There is a new version of AdWords Editor available, version 12.1, that comes with support for several features, such as Shopping showcase ads and expanded dynamic search ads.
With showcase ads, three product images can be featured from a retailer that are related to the search query and link to a Google-hosted landing page of products the advertiser has grouped together. Showcase ads were first introduced in July 2016, but they continue to gain visibility.
If you want to set up showcase ads in Shopping campaign ad group, just select “Showcase” from the “Ad group type” drop-down.
Showcase ads are available as an ad type option in the let navigation. Advertisers can upload a a header image (the main image that represents the product category or brand) right in Editor.