transparent @ 17x17, for using in email address
<a href="//commons.wikimedia.org/wiki/User:Yuval_Y" class="mw-redirect" title="User:Yuval Y">user:Yuval Y</a>
based on <a href="//commons.wikimedia.org/wiki/File:At_sign.svg" title="File:At sign.svg">image:At sign.svg</a>