Never have to worry about stains, pretty neat stuff.
http://www.youtube.com/watch?v=_d-hZCuTZpc
<iframe width="853" height="480" src="http://www.youtube-nocookie.com/embed/_d-hZCuTZpc?rel=0" frameborder="0" allowfullscreen></iframe>
http://www.youtube.com/watch?v=_d-hZCuTZpc
<iframe width="853" height="480" src="http://www.youtube-nocookie.com/embed/_d-hZCuTZpc?rel=0" frameborder="0" allowfullscreen></iframe>