The following information gives you a little more detail with regard to the specs for the ad units:
Sizes: 300x250, 970x90, 728x90, 300x50
Format-any of the file types listed below are acceptable.
.jpg (static or animated)
.gif (static or animated)
.swf (flash ad)-Flash ads also need to be accompanied by a static image such as one of the types listed above.
Third party tags are also accepted
Click-through URL: please provide a URL for the ad to link to
Options 8 offers over 100000 recognized brand items.