This ad is 2 separate pieces made up of full pages. The first image shows 1 page of the ad- that opens up like book to show the 2 connected pages of the 2nd image- the other side of the "book" cover is the front cover of the magazine. The 3rd image shows the 2nd full page of the ad, and the 4th image shows the other side of that page.
A full page is about 8 inches by 10.5 inches.