<iframe id="existing-iframe-example"
width="640" height="360"
src="https://www.youtube.com/embed/-SFcIUEvNOQ?autoplay=1&mute=1&enablejsapi=1"
frameborder="0"
style="border: solid 4px #37474F"
></iframe>
<iframe width="560" height="315" src="http://www.youtube.com/embed/GRonxog5mbw?autoplay=1&loop=1&playlist=GRonxog5mbw" frameborder="0" allowfullscreen></iframe>