title: Issues with Out-of-page placements in DFP
body: <p>I'm in the process of testing my company's ad tags running through DFP, and have had some issues with the out-of-page process which some of our Publishers want to implement. I have everything working properly, but I'm wondering if I misconfigured something because a few things don't make sense to me. Here's my current setup:</p>
  
  <p>I created a new Ad Unit and specified a size of 1x1 because it seems you have to specify a size, even if the ad is served out of-of-page. I then attached a placement to it.</p>
  
  <p>I added a new Order and a Line-item, and then targeted the inventory to the Ad Unit I had created.</p>
  
  <p>I then added a new Creative with a type of Custom, and set the target size to be <code>Out-of-page</code>.</p>
  
  <p>After approving everything I selected the Ad Unit I wanted and hit <code>Generate Tags</code>. This gives me a popup with all the code I need. There is an <code>out-of-page unit</code> checkbox that I discovered I need to enable for this to work. What's weird is that when I check it, the resultant script and code defines two ad-slots:</p>
  
  <pre><code>googletag.defineSlot('/9999999/out-of-page_26297', [1, 1], 'div-gpt-ad-9999999-0').addService(googletag.pubads());
  googletag.defineOutOfPageSlot('/9999999/out-of-page_26297', 'div-gpt-ad-9999999-0-oop').addService(googletag.pubads());
  </code></pre>
  
  <p>and</p>
  
  <pre><code>&lt;!-- out-of-page_26297 --&gt;
  &lt;div id='div-gpt-ad-9999999-0' style='width:1px; height:1px;'&gt;
  &lt;script type='text/javascript'&gt;
  googletag.cmd.push(function() { googletag.display('div-gpt-ad-9999999-0'); });
  &lt;/script&gt;
  &lt;/div&gt;
  &lt;!-- out-of-page_26297 out-of-page --&gt;
  &lt;div id='div-gpt-ad-9999999-0-oop'&gt;
  &lt;script type='text/javascript'&gt;
  googletag.cmd.push(function() { googletag.display('div-gpt-ad-9999999-0-oop'); });
  &lt;/script&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>What's confusing me is that it seems like I only need the out-of-page ad slot. The 1x1 doesn't actually seem to do anything, and if I just comment out the <code>googletag.defineSlot()</code> call, I still register impressions correctly. I'm going to have to write up a tutorial for our Publishers, and I'd really like to avoid confusing them, and having multiple ad slots for one ad seems wrong. Is there some way to avoid this happening? Did I set something up incorrectly? Does google really need both of those placements for out-of-place, or is it a bug?</p>
  
  <p>One other thing I noticed is that when I go to the Inventory tab, and select Generate Tags from the left menu, I don't get the option to select Out-of-page. It's only available when you generate tags from the individual ad placement, which is incredibly confusing.</p>