<div class="addthis_sharing_toolbox">
    <a class="addthis_button_facebook"
        addthis:url="http://google.com/"
        addthis:title="Here's a title"   
        addthis:media="http://images.google.com/example.png" 
        addthis:description="Here's a cool description">
        <i class="ico ico-facebook"></i>
    </a>