Weird float padding 1140 grid system
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Im building a page with the 1140 grid system and I'm trying to add in floated images to the sides of my articles for the benefits section of the page. All the right floated images seem to have a small padding margin where the background is showing through. Ive had no luck tinkering around and wondered if anyone could offer up some help or explain where I'm going wrong. The images should look how the left floats look with the flat side flush to the side of the container. 

NOTE it looks worse in Webkit, firefox for some reason seems to be okay. 

The page can be seen here www.adambrace.dreamhosters.com/PCP 

Thanks 

 