My Dog Says Shampoo Bar is a solid shampoo producing 20 washes, even more for smaler dogs.
Leaving the coat soft and shiny, the solid bar reduces waste. 
Tea Tree, Eucalyptus and Clove oil have been added to help reduce skin issues that cause that itch that some dogs can't seem to scratch.
Rub the bar over the dogs wet coat. Massage in then hose off. Place back in the bag for the next use.
No wasteage - use what you need - good value.