Rare Adword's ad format

As I was searching through Google this morning,a rare adsense ads came up at the side bar which had the facility to call the advertiser directly from it without the need to log in anywhere.After more investigation into the new feature,it came to my attention that this was the new feature tested by Google called "Google Click-to-Call".

Google:"

Google is testing a new feature that lets you speak directly over the phone, for free, to businesses you find on Google search results pages. When this feature is available for a business, you'll see a green phone icon in their advertisement or a call link next to their contact information. Here's how it works: Click the phone icon or call link ........for more continue"