This PolyJohn sink gets hooked up to a fresh water source that uses a drain for gray water. The sink can hold a small amount of fresh water in the tank that is controlled by a float operated valve. The sink basins are plumbed and the water exits in the rear of the tank. This portable sink can conveniently be made into a stand alone sink by the use of a vinyl liner. The sink can be transported by its recessed handles. There is space for strippped advertising. Its 3 ribbed design makes it strong and it is easy to service and to fill with water.