Perhaps a label and a "no water" symbol? Like this: http://thumb15.shutterstock.com/thumb_small/290671/290671,1263638117,28/stock-vector-vector-illustration-of-

Perhaps a label and a "no water" symbol? Like this: http://thumb15.shutterstock.com/thumb_small/290671/290671,1263638117,28/stock-vector-vector-illustration-of-modern-icon-depicting-a-not-pouring-liquid-signal-44588677.jpg http://thumb15.shutterstock.com/thumb_small/290671/290671,12...